A.B.S , C.A.N and other electronic systems

             Honda Multiplexing Board Worksheet

This multiplex system was used for body controlled functions on 1996 to 2002 Honda

accord and 1996 onward prelude. It utilises three nodes (control units) drivers door,drivers

side and passenger side.The testing procedure is divided in to three sections

Communication lines and nodes from mode 1,inputs from mode 2. If the system passes

these tests from mode 1 and 2, but is still faulty the problem is likely to be an output.

1: Using the wiring diagram identify the plugs/ pins and wire colours for the communication

lines between the nodes.

Door . Brown  A15-A2

Passengers. Pink B1-B9

2: Using the wiring diagram identify the plugs/ pins and wire colours for the Earths and

voltage supply lines between the nodes.

The blacks wires are all earthed.

Power is Pink wire A1 to the Door

Door -   A12 to Ground G401 , A19 to ground  G551 (LHD) , and to G581 (RHD)

B22 to Ground

Passenger -A24 Pink wire and Yellow A22

A8 to G401

3: Ask your instructor to create a fault in the unit

Describe in detail how this fault is affecting the normal operation of this system

The drivers side rear door light wasnt working , so when the door is open it wouldnt light up like the rest

4: Using the wiring diagram analyze the fault and describe in detail what may be causing

this fault.

It could be that the grounding is bad , or the wire being broken also there could be a break from the multiplex to the rear door switch

5: After reading the manual put the system in to test mode 1. Note the codes (if any) and

possible faults that the system gives you.

There were no codes
6: Do the codes concur with what you thought the problem might be from question 4,

explain.

There are no codes coming up
7: Go to step 5, can you conduct this test? Why /why not.

Yes , all the communacation lines were good
8: Conduct the tests in step 6, what is your results and conclusions.

Communication line

Door- Drivers , Brown wire was good , it was 5.2v and with the spacification of 3.5-9.5v

Drivers passenger side , pink wire was also good and was 5.2v aswel within the spec of 3-10v

9: Put the system in to diagnostic Mode 2, conduct the input tests and note the results.
We just turned the ignition on to wake up the system

Controlled Area Network Board

Using the dual trace feature on the oscilloscope capture the full pattern of the H-CAN and L-CAN. Identify which wire is the H-CAN and which is for the L-CAN

Top one is L-CAN and the Bottom is H-CAN

On your capture also identify were the data pattern starts and finishes

Describe the relationship between the two patterns and their base voltages (what volts when not switched)

They mirror each other if one goes up the other will go down and vise versa

For each of the following inputs capture the pattern and identify were it changes in relation to the original pattern:

Right indicator

Left indicator

Rear wiper

Stoplights

Fuel pump

Reverse lights

Using the wiring diagram and CAN board Identify the input /output pins, wire colours, Relay or transistor for the right hand indicator and rear wiper:

The right hand indicator is connected to pin 7 , it goes to a resistor R5 then goes into the chip 18F258 in pinout 6 , RA4/TOCKI. It then comes out from RB2/CANTx pin 23 and Rb3/CANRX pin 24 . CAN-H comes out of pin 7 to chanel 1 and can low to pin 6 to channel 2. Then comes out of pin 4 & 5 to chip IC5-UC335ON . 7 Can H and 6 Can L goes into the input pin 13 TXCAN and 4 to 12 RxCAN then comes out from GP4/REF 5 to a 1k Resistor R32 then goes to a opticoupler IC9 then to a pull donw resistor on its way to the transistor and then goes to the output connector 5 which is right hand indicator.

The rear wiper is on Pin 9 which goes to a Resistor (R8)then pin 25, RB4 on chip VP18F258 then comes out of RB32/CANTX pin 23 & RB/CANTX pin 24 then to pin ! TXP and 4 RXD on the chip IC4 then it comes out from Can H & Can L on pin 6 to the standard termination to the Can Connector 1 & 2 then output is from 4 & 5 which goes out to 7 & 6 Can H and Can L then comes out TXDI1 & RXD pin 4 then goes into the cip IC5 . 13 TXCAN & 12 RXCAN , out pin 10 , GP6/CLKOUT to a resistor R35 K then to a transistor to the ase. Emitor goes to ground and the collector goes to the relay then 7 on the output connector .

TXD- Transmit

RXD - Receive

Using the wiring diagram identify both voltage regulators that resemble the one that you built in TTEC4824. Note all the input pins and were the outputs are connected to

U1 7805: Input from supply from pin 1 & 2 , output goes to pin 1 & 20 on chip VP18F258 and pin 3  in IC4 Chip. One to 16 on chip IC3.

U2 7805 - Input from 12v pin 1 & 2, output in pin 14 vdd

Using the wiring diagram follow one circuit though from the input to the output. Note all the inputs/IC/relays/transistors and describe how the circuit operates

I did the fuel pump on pin 8 which goes to a resistor (R6) then to pin 7 RA5/AN4/SS on the chip (VP18F258) then comes out of RB2/CANTx pin 23 & Rb3/ CANTX pin 24 then to pin1 TXD and 4 RXD on the chip IC4 then out from CAN H 7 & CAN L pin 6 to the standard termination to the can connector 1 & 2 then comes out of 4 & 5 into 7 Can H and 6 Can L to the chips IC5 then comes out TXP1 to pin 13 , TXCAN then out to Gp3/ REF16 to R32 a 1k Resistor then to a transistor then a relay to output 6 that is the fuel pump

CAN – Multiplexing Worksheet

1.0  CAN Waveform on Oscilloscope 

1.1  Locate the Range Rover or other suitable vehicle with easily accessible CAN system twisted wires.  Which vehicle do you have? (Year, make and model) Range Rover , 2001 . V8 Rouge

1.2  Locate a twisted wire pair. Describe where the wires are located:  It was located near the Abs Module

1.3  Record the waveform of one of the wires below: (Make sure your time is small enough so you don’t have “aliasing”.)

The top line on the picture

Colour of wire: Yellow/Brown

Time per division: 10ms

Voltage per division: 2v

1.4  Record the waveform of the other wire in the twisted pair.

Bottom line in the picture

Colour of wire: Yellow/Black wire

Time per division: 10ms

Voltage per division: 2v

1.5 What is aliasing? Describe it. 

Aliasing happens when a signal is taken at a less then twice the highest frequency present in the signal. 

(http://www.wfu.edu/~matthews/misc/DigPhotog/alias/)

1.6  How do you know these waveforms are not “aliasing”? 

When you look at the graph and see the wave form it is not aliasing

1.7 In the 1.3 waveform above, what is the main voltage on the line?

2.37v

What is the other voltage on the line, when the voltage is pulled up or down to “talk” ?

 1.7v

1.8  In the 1.4  waveform above, what is the main voltage on the line?

            2.64

What is the voltage on the line, when the voltage is pulled up or down to “talk”?

            Pulled up 4v

1.9  Observe the signals in 1.3 and 1.4 above with a voltmeter. Compare it with DC volts or AC volts setting. Which setting would tell you if the signal is switching. Explain: 
You can see the signals switching , the means the Ac voltes are pulled up & down 

2.0  Scan Tool Observations      

2.1  Find a vehicle that will show CAN system operation on a scan tool (such as the Range Rover. 

Which vehicle are you using? Land Rover

Which scan tool are you using? AutoBoss

2.2 What different functions are available on the scan tool to examine the CAN system?  
The scan tool can show you all the faults

2.3  List the different systems that are controlled by CAN? (note which are high speed and which are low speed)

Low Speed :                                                             High Speed :
Wipers , Window Sprayer Indicators                Brake Switch, ESP,ABS,Fuel pump, Radio

         Antilock Braking Systems Lab Workbook (4825)

Off-car Exercises
Think about ABS Repair:

Misconceptions, The ABS system should be simple and robust, with the Module/ECU/Controller
almost never giving any trouble.
Below are some possible causes for damaging an ECU.
• Spiked by careless welding, i.e. MIG welding without disconnecting the battery. True/False
• Enclosure seal damaged and with obvious sign of water ingress.
True/False
• Obvious signs of mechanical damage to the enclosure.
True/False
Often the ECU will be misdiagnosed as faulty, usually because the technician is inexperienced in
faultfinding.
• Faults are much more likely to be with connections or sensors.
True/False

ABS Wiring and Operation

Fill in the blanks with the name of the part:
1 = Brake Rotor                    6 = Brake Assembly
2 = Wheels sensor                 7 = Brake Booster
3 = Tooth Ring
4 = Hydrolic module
5 = Master Cylinder

Wiring Diagram Practice
There are a number of components in the ABS systems that are also used for fuel injection. These
are mostly speed sensors e.g. wheel speed and engine speed.
Using the wiring diagram in the workshop manuals identify the wheel speed sensors and list their
wire colours for each sensor
Front right Green 23a Red 22a
Front left White 9a Black 10a
Rear left Blue 3b Pink 2B
Rear right Yellow 8b Brown 9b
On the ABS wheel sensor what is the reason for the braded wire?
To reduce noise and also stop interferance from other signals
Identify and list all the fuses that are used by the ABS circuit
FL Main, F14 50A ABS, 10A gauge, 20A DONE, 15A STOP and 15A ECU-IG
Identify the earths for the ABS control unit and ABS motor their wire colours what pins numbers
Abs Motor - IA white and Black 

Abs Ecu - 10B & 7B white & Black

On the wiring diagram for the ABS actuator, identify which solenoids control which wheel cylinder.
Then note the wire colours and pin numbers

Front Right Wheel
Pin number: 2B, 6B
Wire colour: Red/White , Red/Green
Front Left Wheel
Pin number: 3B/7B
Wire colour:Blue/Red , Blue/White
Rear Left Wheel
Pin number: 4B,8B
Wire colour: Green/Black , Green/Yellow
Rear Right Wheel
Pin number: 1B,5B
Wire colour:Brown/White , Brown/Red

On the graph below draw a digital signal that switches 5 volts every 2 seconds.
Mark volt and time scales on graph that will show the signal well.

Bottom line is Zero Volts then goes up to 5

On the graph below draw an analogue signal with a frequency of 0.5 Hz and a maximum of +3
volts. Mark volt and time scales on graph that will show the signal well.

ABS Demonstrators

We tested ABS from a 1992 Open Vtectra
Locate the wiring diagram for your demonstrator vehicle. Find the ABS wheel speed sensor pinout
connections to the ECU on the wiring diagram and the demonstrator. Record which ECU wires
go to which wheel speed sensors:
Left front ECU Pin # (B19) 4 and 5
Left rear ECU Pin # (B21) 7 and 9
Right front ECU Pin # (B20) 11 and 21
Right rear ECU Pin # (B22) 24 and 26
By looking at the wiring diagram, what type of speed sensor is this?
Magnetic pick up sensor
Describe how it works:
When the rotor is spinning , the teeth sends out a magnetic feild to the abs module to see if all the wheels are at the same speed.
Locate an oscilloscope. Turn it on and set it up to be fully operational. What oscilloscope are you
using? Seintek S2800 Automotive scope

Which wheel is this? Left Front . #9 Ecu pin 5

Which wheel is this? Left rear . #7 Ecu pin 7

Which wheel is this? Right Front. #8 Ecu pin 11 . ( high voltage , could be corrosion)

Which wheel is this? Right Rear. #6 ECU pin 24

Are all the waveforms exactly the same? Yes ____ No ✓ Discuss what are the differences,
and what can cause these differences between the waveforms:
The right front wheel speed sensor was giving a higher voltage reading than the rest. This could be that there is some corrosion on it or its to close to the rotor
With the wheel speed sensors spinning, measure AC volts with a multi-meter and record here:
Left front 5.44v
Left rear 4.30v
Right front 16.48v
Right rear 6.29v
Can a multi-meter be as accurate in finding problems with the wheel speed sensors as an
oscilloscope? Yes ✓ No ____
Discuss what the oscilloscope could find that the multi-meter can not find and why:

The Oscilloscope shows the spinning of the teeth. You can see the waveforms

ABS Relays
Record the name of the relay or switch that powers up the ABS ECU: (look at the wiring diagram)
K39. Protection Relay
Record the name of the relay or switch that powers up the ABS pump: (look at the wiring diagram)
K100. Pump motor Relay
Record the name of the relay or switch that sends power to the ABS HCU solenoids: (look at the
wiring diagram)

Relay wire identification: (Consult the wiring diagram)
What is the ECU pin number for the wire that brings in the power to the ABS ECU?
S13. Brake Pedal Position Switch
What is the ECU pin number, or other number, for the wire that controls the relay for the ABS
ECU?
Pin 1
What is the pin number for the wire that brings in the power to the ABS Pump?
Pin 14
What is the pin number, or other number, for the wire that controls the relay for the ABS Pump?
Pin 28

Relay waveform: Capture a waveform that shows both the control circuit change when it turns on
the relay, and the power switching on to power something in the ABS system. (Use an oscilloscope
with two channels to capture this pattern. You may have to carefully set the trigger to capture this.)
Record the waveform below with the time and volts per division, and explain what you are
measuring.

Explain with arrows what is happening in the waveform above.
The top line is the switch and the relay is the bottom line.

ABS Pump Relay waveform: Capture a waveform that shows both the control circuit change
when it turns on the relay, and the power switching on to power the ABS Pump. (Use a oscilloscope
with two channels to capture this pattern. You may have to carefully set the trigger to capture this.)
Record the waveform below with the time and volts per division.

Explain with arrows what is happening in the waveform above.
Tutor wrote it on the board for us

On vehicle testing:
LIFTING & SUPPORTING VEHICLES

To safely lift and support a motor vehicle on a flat surface
Vehicle : Daihatsu Model: YRV
Ensure the floor surface is clean and flat
Apply the parking brake; slacken wheel nuts of wheels to be removed
Identify a safe vehicle chassis member to lift the vehicle using the jack
Lift the jack until it is touching the chassis member
Release the parking brake to allow the vehicle to roll while lifting
\recheck the location of the jack before lifting the wheels off the ground
Locate axle stands in a safe position on solid vehicle member
Have your tutor check before lowering the jack
Lower the jack slowly until the vehicle is supported by the stands

To safely lower the vehicle to the ground after being supported on axle stands:
Ensure all wheels and nuts are located before removing vehicle stands
Lower the vehicle gently to the floor
Apply parking brake
Torque and check wheel nut tightness

On-Car Exercises
On the vehicle that you have been assigned identify the following components to your tutor:
Wheel speed sensor✓
ABS control unit✓
ABS modulator✓
ABS pump motor✓
Parking brake switch✓
Brake master cylinder✓
Brake fluid level switch (if fitted)✓
RPM sensor✓
Foot brake switch✓
Brake booster✓
Main ABS control unit fuse
Instructor OK? ✓

ABS Wheel Speed Sensors
On the vehicle that you have been assigned does it use analogue or digital wheel sensors?
It was Anolouge
How did you conclude that the wheel sensors were analogue or digital?
Anologue , Because the tooth of the ring
Using an oscilloscope connect it to a wheel sensor and record the pattern shown, If the sensor is a
Analogue sensor then just connect then probe and spin the wheel. If the sensor is digital you will
need to have the ignition on before you turn the wheels. (show scale)
Is this pattern an analogue or digital pattern?
Analougue

PCM = Powertrain Control Module
TCC = Torque Converter Clutch
TPS = Throttle Position Sensor
ECT =  Engine Coolant Temperature Sensor
VSS = Vehicle Speed Sensor
PSA = Powertrain Control Module
TTS = Transmission Temperature Sensor.

On-Car Exercises

First we Connect a Scan Tool to the car brang up the transmission information.

Which scan tool are you using: MultiScan p1
Which vehicle are you using: Mitsubishi lancer Wagon 2008
2.2 With the vehicle safely on jack stands or a lift (use the proper worksheet for that), safely drive
the vehicle to allow it to shift up and down through the gears. View the solenoids as the vehicle
shifts up and down. Record which solenoids are on in which gears:
With the shift lever in Drive or Overdrive:
First gear solenoids: 2nd OD
Second gear solenoids: LR  OD
Third gear solenoids: 2nd  LR
Fourth gear solenoids: UD  LR
View the Torque Converter Clutch as you safely drive the vehicle. Record when it is on or off:
Torque Converter Clutch On:
The solenoids turn on at a higher gear
Torque Converter Clutch Off:
When you slow down the solenoid will turn off

Picture Taken from google images

 

10: Explain your results and conclusions, Does it concur with your diagnosis from question 4?

It is the input. The switch could be faulty as the rest work but drivers side rear doesnt . We tested all the communication lines and they were all ok
11: Using the wiring diagrams from the back of the manual describe what tests you would

carry out now and what results you would expect. Note wire colours and pin/block

numbers.

A14

12: Put the system in to sleep mode and measure the time it takes and the parasitic draw,

Explain why this system is necessary.

4.03v

10 seconds

.66amps

.018amps

 Explain how this test could be used.

On Car II

                                  Exhaust Gas Analysis

Exhaust gas is emitted as a result of the combustion of fuels such as natural gas, gasoline/petrol, diesel fuel, fuel oil or coal. According to the type of engine, it is discharged into the atmosphere through an exhaust pipe, flue gas stack or propelling nozzle.

Exhaust Analyser should be warmed up and recently calibrated. When it’s time to start taking tailpipe readings, put the analyser probe into the tailpipe and install exhaust tube over probe to capture exhaust fumes. Make sure there is adequate ventilation.

Note: make sure you fill out the “means: .............  segment to explain what that gas reading means. Example, if you are measuring HC, which shows us about misfire in the engine, and you had a low number like 28 ppm, you would say “shows low amount of misfire”, or “most of the fuel is being burnt.” But if the HC was high, like 340 ppm, you might say “There is a high amount of misfire” or “not all the fuel is being burnt.”

Readings are from a Ford KA & Toyota Corrolla FXGT AE82 with a 20valve silver top

1.         With the analyser probe sensing normal air, what are the Four Gas readings? Record the amount and then what it means:

CO 0.00   means: There is no CO in the atmoshpere HC 13ppm  means:  Higher HC means that unburn fuel remains in the exhaust gases.CO2 0.00%means: EfficencyO2 20.91   means:  It is lean

2.         Start the engine idling cold, and record the Four Gas readings

Explain what is happening within the engine referring to the four gases:    

CO 4.46%  HC 1839  CO2 9.88  O2 9.26 

Co is high becuase O2 is low , as the engine starts cold the CO increase to 4.46%. Hc is also high which means that rich mixture enters the combustion chamber. The CO2 (efficency) is low because there isnt enough o2 and the O2 is high from the inactive catalytic converter , cause by the unburnt gaeses

        

3.    When the engine has warmed up, record the Four Gas readings:

Explain what is happening within the engine referring to the four gases:      

CO 0.162  HC 79  CO2 4.02  O2 1.10 

Now that the engine is warmed up, the CO & HC decrease. This means that the ideal mixture enters the combustion chamber and the cat convertor is working therefore the engine is running efficently. The CO2 is high and the O2 is low because the most of the fuel is being burnt.

4.    Run the warm engine at 2500 RPM, record the Four Gas readings:

Explain what is happening within the engine referring to the four gases:      

CO 2.5  HC 173  CO2 12.71%  O2 1.63 

Co is low and more o2 as the engine is running warm at 2500 rpm, the CO and HC Increase due to higher RPM with more emissions. CO2 is good and O2 is low becuase of the gaes being burnt

5. At idle, run the mixture rich with extra propane, LPG, or carburettor cleaner,  and record the Four Gas readings:

Explain what is happening within the engine referring to the four gases:      

CO 1.8  HC 224pmm CO2 225  O2 0.79 

  Engine is running rich because we had disconnected the vacuum hose in the fuel regulator , Hc is higher which makes it less efficient. The CO also increases to 1.8 which means that is is a rich mixture.

6.    At idle, create a lean condition with an air leak or vacuum leak, record the Four Gas readings:       

    Explain what is happening within the engine referring to the four gases:        

CO 0.175 HC 959  CO2 7.75  O2 9.65 

When the engine was at idle we disconnected  the PCV valve to make it run lean. The CO is  nomal ,the unburnt fuel goes up and CO2 is reduced but the O2 increases significantly which means that is has a lean mixture. 

7.    Accelerate the engine, by blipping the throttle a few times (don’t rev too high anddamage the engine), and watch how the gas readings change.  Record the Four Gas readings when the CO is highest: 

    Explain what is happening within the engine referring to the four gases:        

CO 3.547 HC 699 CO2 12.39  O2 0.58
 We suddenly accelerate and let go, there is a rich mixture going into the combustion chamber and HC rise. The CO is reduced as there is less O2 .

8.    Disconnect one spark plug wire, ground it with a jumper wire, then record the Four Gas readings as the engine idles:

     Explain what is happening within the engine referring to the four gases:       

CO 0.582  HC 1291  CO2 12.04  O2 7.61 

Co is high because there is low 02 as the misfire is produced in a cylinder, the HC increases  because the unburnt fuel is created by the misfired cylinder. The O2 is also produced more from the air/fuel mixture of the misfired cylinder.

9.    If you can get to it, disconnect the injector harness connector from one injector on an engine that has one injector for every cylinder: Record the Four Gas readings as the engine idles:

Explain what is happening within the engine referring to the four gases:      

CO 0.247  HC 217  CO2 11.68  O2 5.17 

The injector is disconnected, Co is low because air is going through the cylinder and the HC is low because less air going through Alos Co2 is low due to effiecient combustion and O2 increases because one cyclinder is not burning.

10. Optional: Make other changes to the engine at idle, such as turning on the air conditioning or rocking the steering wheel.  Note the change you made: 

    Explain what is happening within the engine referring to the four gases:        

CO 0.300  HC 74  CO2 14.73  O2 0.12

Overall the readings were all good, the emission is clean with proper values. However, when loads (air conditioning and rocking the steering wheel) are added, the rpm will go up. As a result , the CO and HC increase slightly with the rich condition.  

Return the vehicle to good condition and proper adjustment.

11.      Explain the different readings you would get from a vehicle with a catalytic converter and a vehicle without one and why?

You would get the differnt readings, without the catalytic converter there will be more Co and HC as the catalytic converter creates a chemical reaction to change the emission into something else which is less harmful to the atmosphere.The catalytic converter helps reducing emissions with its chemical actions.

12.      Explain what light off point means and what happens?

 For the catalytic convertor to work the temperature should be hot to work, the catalytic converter will clean the emissions by reducing toxic gases in the exhaust system with its operating temperature.

13. On lambda, 02 sensors why do they have 1,2,3,4 or 5 wires and what do these extra wires do?

 One is heater positive and there is a negative, the O2 sensor works correctly and increases responses with operating temperature when the engine starts cold.The black wire is a snesor signal positive which gives the state of exhaust gases to the ECU. The gray wire is a sensor signal earth
                                                           Oxygen Sensor

An oxygen sensor,is an electronic device that measures the proportion of oxygen (O₂) in the gas or liquid being analyzed.

1.1 Locate an oxygen sensor on your vehicle. Describe where it is located:

  It is located in the exhaust manifold or in the exhaust downpipe before the catalytic converter.

1.2 How many wires for this oxygen sensor?  4

1.3 Record the colours for each of the wires at the sensor side of the connector (not the ECU side of the connector).  Then list the use of the wires. Usually a black or blue wire will be the O₂ sensor signal, Grey may be the sensor ground. Heater power and ground are often white. But there may be other colours. You may have to consult a wiring diagram.

          Colour                           Use or Purpose                       

          White                                          Heater Positive (+)
          White                                          Heater Negative (-)          
         Grey                                           Signal Negative (-) 
         Black                                          Signal Positve (+)      

1.4 What type of Oxygen Sensor is this? (tick one)

                   Zirconia switching sensor?                               ✓
                   Titania switching sensor?                                 …….

                   Broadband Air Fuel Ratio sensor? (one cell)  …….

                   Broadband Air Fuel Ratio sensor? (two cell)  …….

2.0 Now we Back probe the Oxygen Signal Wire with a pin and connect to an oscilloscope. If you need help using the oscilloscope see your lecturer or other help sources. Check that you are connected to the Oxygen sensor signal: Run the engine and check that you are seeing a signal. Connected OK? Yes  ✓

3.0 Watch and Record Oxygen Signal pattern at 2500 rpm. Let the engine warm up and enter closed loop so you see a normal cycling pattern. You may have to hold the rpm about 2500 for half a minute to go into closed loop.

         

3.1 Freeze your pattern and draw or photograph it onto the graph below: Note the voltage and time per division or scale next to the graph.

3.2 How high does the voltage go? 0.8v

3.3 How low does the voltage go?  0.2v
          3.4 What is the average voltage? 0.4v

3.5 How many “Cross Counts” does the signal have in 10 seconds? (One cross count is when it goes from high to low, or from low to high.) List here: 30

3.6 If the signal is not cycling normally, describe what the signal does:

         If it Misfires in one cyclinder , the cycle will have dips in it. 

       

4.0 Watch and Record Oxygen Signal pattern at Idle rpm. Let the engine warm up and enter closed loop so you see a normal cycling pattern. You may have to hold the rpm about 2500 for half a minute to go into closed loop. Then let the RPM come down to idle.

4.1 Freeze your pattern and draw or photograph it onto the graph below: Note the voltage and time per division or scale next to the graph.

4.2 How high does the voltage go? 0.8v

4.3 How low does the voltage go?  0v

4.4 What is the average voltage? (Some oscilloscopes have functions that will calculate the average for you. If not, just guess.) 0.4v

4.5 How many “Cross Counts” does the signal have in 10 seconds? (One cross count is when it goes from high to low, or from low to high.) List here: 7

4.6 If the signal is not cycling normally, describe what the signal does:

          It may have a negative pattern on the graph .

          5.0 Make this Oxygen Sensor go rich by accelerating once or twice. (The fuel system should normally make the system go rich when you do a sudden acceleration.) Push on the accelerator quickly but don’t let the rpm go high enough to hurt the engine. (If you act like you will hurt the engine you will be asked to leave lab.) The signal should go over 0.85V.

         

5.1 Freeze your pattern as it goes rich and draw or photograph it onto the graph below: Note the voltage and time per division or scale next to the graph.

          5.2 How high does the Oxygen sensor voltage go? 0.9 V         

5.3 If this signal is not going high normally, describe what the signal does: 

        It will have a very low voltage and it will be lower than 1.0 volt.
 

   6.0 Make this Oxygen Sensor go lean by doing sudden deceleraton. Gently run the rpm to about 3000 , and let the rpm drop suddenly. The fuel system should make the system go lean on deceleration. The signal should go below 0.2 V


6.1 Freeze your pattern as it goes rich .

6.1 How low does the oxygen sensor voltage go? 0.2 V
6.2 If this signal is not going low normally , describe what the signal does:
The signal will be above zero volts , might be a slugish oxygen sensor

7.0 Measure the Response Time of the sensor. freeze the pattern and measure how long it took the sensor to go from lean to reach.

7.1 freeze your pattern as it goes suddenly rich from a lean condition and draw it into the graph below . Normally you want the voltage to go from below 0.2 V to above 0.8V. In less than 100 ms .

7.2 Measure how long the sensor took to go from lean to rich. Use the sensors coursers on the scope if necessary. Record how long the sensor took here: 1.50 ms

8.0 Discusses how a normal Zirconium oxygen sensor works: draw a picture below to help show how it works?Zirconium oxygen sensor has two electrodes which provide an output voltage corresponding to the quality of oxygen in the exhaust in relation to the atmosphere. The output of 0.2 V represent a lean mixture. The Zirconia oxygen sensor technology operates though a known voltage being generated through oxygen interaction with the ziconium when it is heated to over 700ºC.

9.0 Discuss how good or bad this oxygen sensor is. What about it function well or is faulty? Use detail and specific voltage in your discussion. Can it accuratelly tell the ECU how rich or lean the exhaust is?

This sensor elements the rich/ lean cycling allowing the control unit to adjust the fuel delivery and ignition timing of the engine much more rapidly, but less sensitive to either rich or lean. 0.2 volts represent lean and 1 volt represent rich mixture.

                               Fuel Pressure and flow

1.         Locate the two closest fire extinguishers.  (If you have to use it remember to pull the pin, squeeze the handle, and spray at the base of the flame.) Write down where they are:

              Front left of the room by the door.

2.         If you can, look up Fuel Pressure specifications for the vehicle you are testing. If you can’t look them up, make a guess at the fuel specs you should have and write them down here:

                   34-44psi

3.         Use eye protection. Optional: Relieve fuel pressure before installing pressure gauge. Or there will be some fuel that sprays at you as you attach the gauge. You can relieve pressure by several methods: 1) To relieve the fuel pressure. Make sure you have a rag to catch the fuel, start the engine. 2) Remove fuel pump (circuit opening) relay or fuse and run the engine until it stops, then crank to check that the engine doesn’t start 3) Use a vacuum gauge on the pressure regulator to lower fuel pressure, or  4) Open a fuel line at some pressure point and catch the fuel in a rag beware there may be lots of fuel.

4.         Attach fuel pressure gauge and notice which scale on the gauge you will be using. Briefly turn key on or start vehicle, then turn it off. Check for fuel leaks.

Are there leaks? Yes ...................... No ✓
If there are leaks you must correct them and retest before continuing.

5.         Measure the fuel pressure with the key on, engine off.

Record it here: 35psi

6.         Idling: Measure the fuel pressure with the engine idling. Watch the pressure for a couple of minutes.

Record pressure here: 38psi

7.         Maximum: With the engine idling, use the special tool to clamp the fuel return line. Note: this can only be done for a short period.                                                            

Record pressure here: 80psi

8.         WOT: With the engine idling, disconnect and plug the vacuum line going to the fuel pressure regulator.

          Record pressure here: 48psi

9.         Residual: Turn off the engine, and watch the fuel pressure for five minutes.

Record your residual or rest pressure here: 42.5psi

10.      Flow: Hook up proper equipment to read fuel volume if necessary. Record flow gauge results of volume, or how much pumped in 15 seconds: (normal results may be ½ liter in 15 seconds)

                                666ml

11.      Replace vacuum lines. Carefully remove the fuel pressure gauge (beware of fuel spraying into eyes, avoid sparks, etc.) Turn engine key on and off, check for leaks.  Start engine, check for leaks. No leaks? Check here: ✓Replace cap over fuel pressure test port. Check when done: ✓Make sure the vehicle is safe and runs fine when done, or tell your instructor.

12.      Explain why it is important to know a vehicle fuel pressure/flow?

To make sure it is running at its maximum capacity , and it is important to keep the fuel being injected into the engine at the correct amount

13.      Describe the symptoms a vehicle would give with each case

Low fuel pressure

It will run lean , it wont idle properly. RPM will be low and it will be running rough and have low performance

Low fuel flow

Blocked fuel filter , weak return vavle in pump , sping cam gets weaker it will always be richer , which means it will use alot of fuel

High fuel pressure

Too much fuel being used running rich , dripping injectors means that there will be flooding , return regulator will be broken.

Faulty fuel pressure regulator

Floading of injectors which will leak out. The injectors causes hard starting , poor economy and useing more fuel which makes it run rich

                                                  Flash codes

We did a test on a Mitshubishi Legnum 1997

1. Flash/Blink Codes

1.1         Find a engine/vehicle that you have the workshop manual with the correct procedure and codes to diagnose the flash codes

1.2         Have your tutor create a fault in the EFI system

1.3         Using the workshop manual follow the procedure to extract the codes, explain briefly what is the procedure

To find a fault code on the engine you will see the engine light flashing.We earth out on the data link connector then turn the key on without starting the vechile. The codes will begin to flash on the check light.

All codes are 2 digit numbers. The codes 55 indicate the end of the message.

2             Trouble Codes or Fault Codes

2.1         Find where the Codes are listed

2.2         Record any codes, and what system and condition they describe in the chart below (Example: might be code number 21, for Throttle Position Sensor, signal voltage too low)

Code number	System affected	Condition described
23	Cam Sensor	Engine wont start
41	TPS	No voltages
31	Intake Air temp	Rough idle , struggle on acceleration

3             Visual Inspection to find fault

3.1         Do a visual inspection under the bonnet to find where the problem is. Use information from the code to know where to look for the problem and what type of problem to look for.

3.2         Describe the problem(s) you found:

 I found out that there were disconnected of some sensors, such as a Cam sensor, TPS,  intake air temperature sensor. 

Check the condition of the wires

4             Repair fault

4.1         Plug back in the connector, or repair problem found

Describe what you did:

After i pluged back in the connector, I have checked the engine condition and retested the signal voltage of sensors. The engine have recovered with appropriate conditions.
I checked the code numbers again , then i dissconnected the battery terminals for 30 seconds and put it back on the battery and tunred the engine to check the light was flashing that means that the codes are now cleared

5             Clear Codes 

Describe what you did to clear the codes:

It was very simple , i just disconnected the neagative lead on the battery and then took the main fuse our for about 30 seconds

6             Recheck for codes and record codes in system now:

After clear codes, E1 and TE1 of diagnosis box should be reconnected. When the ignition switch is turned on and the engine is not running, the check engine light is contantly flashing that means normal condition of the engine without any faults. I rechecked the codes and found there was no codes which mean they were all cleared

7             How could the faults found affect the engine performance?

           

The engine wouldnt run properly which mean low engine performance and it could also create idling problems and will misfire

8             Discuss what other tests you should be doing once you have found the fault codes:

After i had did the fault check , i had to check the voltages to see if it was within the speciification on all the sensors to check if they were any faults and all the sensors function correctly

                                                            Scan Tool Diagnostics

Make Mitshubishi  Model Legnum .Year 1997

Fill in the letters used to label the information and the value of that data. (For example, engine load information may be found under MAP, with a value of

1. Scan Tool Data

1.1 Find a vehicle which is appropriate for the scan tool.

1.2 Connect the scanner, power it on, follow the instructions and input the correct vehicle information it asks for so you can view the data.

1.3 Find the data for the information listed on the next page.

Turn engine on to

3.6, listed in volts) Note: not all vehicles will support all information, just find as much as you can. If the engine won’t

run, input the information with the key on, engine off.

Type of information (PID = Parameter Identification)	Letters to describe it E.g. TPS	Value of data	Units for data E.g. volts
Engine Load (how much air comes in)	MAF	1.3	V
Engine RPM	Crank	.068	RPM
Throttle angle	TPS	624	Mv
Engine coolant temperature	ECT	71	°C
Intake air temperature	IAT	27	°C
Fuel Injection opening pulse	Injection	0.5	Ms
Transmission select position	Manual	Neutral	N
Vehicle Speed	Km/H	0	KM
Oxygen sensor(s)	O2	351	MV
Fuel Trim	-	-	-
Idle control	ISC	42	STEP
Power steering condition	-	On	-
Air conditioning condition	AC signal	OFF	ON/OFF
Exhaust Gas Recirculation (EGR)	-	-	-
Fuel Evap or Purge condition	-	-	-
Malfunction Indicator Light (MIL)	Check Engine Light	OFF	ON/OFF
Barometric Pressure	Pressure Sensor	99	KPA

2             Trouble Codes or Fault Codes

2.1       Find where the Codes are listed

2.2       Record any codes, and what system and condition they describe in the chart below (Example: might be code number 21, for Throttle Position Sensor, signal voltage too low)

Code number	System affected	Condition described
23	Camshaft Sensor	Low Voltage

3             Lecturer put in Fault

3.1       Find your lecturer and have him create a fault under the hood (don’t look)

4             Record New Codes

4.1       Look up the codes now in the scan tool

4.2       Record the codes in the chart below. Also record what system is affected, and what condition is described.

Code number	System affected	Condition described
31	Vaccum Sensor	High Voltage, Causes engine to stall
22	Coolant Temp	High Voltage

5             Find What Data Has Changed

5.1       Look through the scan tool data to see what PIDs (Parameter Identification of system voltages) have changed. Which readings don’t make sense or don’t read what you would expect. Concentrate on the PIDs related to the codes.

5.2       Record the PIDs that have changed below:

Type of information (PID = Parameter Identification)	Letters to describe it	Value of data	Units for data
Intake Manifold		46	KPA
Coolant Temp	ECT	0	°C
Engine Speed	RPM	825	RPM

6             Visual Inspection to find fault

6.1       Do a visual inspection under the hood to find where the problem is. Use information from the code to know where to look for the problem and what type of problem to look for.

Describe problem you found:

MAP & ECT is disconneted.

7             Repair fault

7.1       Plug back in the connector, or repair problem found

7.2       Describe what you did:

Pluged connectors back

8             Recheck Data PIDs

8.1       Recheck the data with the scan tool

8.2       Record the voltages for the PIDs related to the problem, to confirm they are back to normal

Type of information (PID = Parameter Identification)	Letters to describe it	Value of data	Units for data
Engine Speed	RPM	825	RPM
Intake Manifold pressure	IMP	27	KPA
Engine Coolant temp	ECT	70	℃

9             Clear Codes 

Describe what you did to clear codes:

         

           I disconnected of the negative terminal  off the battery and took out  the engine main fuse for 30 seconds

10         Recheck for codes and record codes in system now:

         

 I rechecked the codes by selecting D.T.C, and there was no trouble codes on the screen.        

11      Discuss the importance live data when fault finding

It shows the state of the sensors from the live data values

12      Explain the need for parameters when checking live data

         So we know the fault is fixed, the live data will be checked with its parameters then the data should be compared to fault datas.

13     Discuss how a scan tool can aid you when fault finding

         

  I can now find the fault easily now even though the vehicle is old or new,or whatever make it is . I can check the state of a vehicle just by plugging in the scan tool and check the data , it is very useful as you can pinpoint the problem.

                                     Primary & Secondary Ignition

1.0 Primary Voltage Patterns

1.1         Set up a lab scope or ignition oscilloscope to view the primary ignition pattern (in parade or display mode) on your lab scope, with the engine warmed up and idling.

1.2         Record the average Firing Voltage (or “Step Up voltage) for each cylinder in the chart below. Some variation is normal, just pick the average. If you don’t understand what this is, review the resource information available.

1.3         Record the average Burn Voltage for each cylinder in the chart below.

1.4         Record the average Burn Time in milliseconds for each cylinder in the chart below

                           

1.5         Record the average Dwell Time for each of the cylinders in the chart below. What unit of measurement are you using to measure the dwell time?

                            Milli Seconds      7ms/20%

1.6         Are all these primary ignition voltage readings normal? Yes ✓No ____  Please discuss what is normal or abnormal about this pattern and what causes it?
             
           The above pattern is the normal pattern for this primary circuit because it has dwell time, firing time, burn voltage and burn time. Abnormal pattern may miss one or more above configrations

Cyl 1	Cyl 2	Cyl 3	Cyl 4	Cyl 5	Cyl 6	Primary Ignition
300+v	300+v	300+v	300+v	-	-	Firing Voltage
47v	50v	55v	57v	-	-	Burn Voltage
1.5ms	1.5ms	1.5ms	1.5ms	-	-	Burn Time
7ms	7ms	7ms	7ms	-	-	Dwell Time

1.7         Draw or photograph the Primary Ignition oscilloscope parade pattern from your scope into the box below. Do it carefully and show the detail you need to see for diagnosis. Record voltage and time scales.

1.8         Discuss what the primary display or parade pattern emphasizes for diagnosis. What can it help you see?
            
            The Primary display tells us how this primary circuit play a role in spark generation in spark plug through secondary wiring. It help us to see the exact voltage pattern on ignition oscilloscope and to find the fault in it if any which is effecting the engine performance

1.10 Some scopes have the facility to use raster or stacked display. How could this help you to diagnose a fault. What can you see more clearly?

2.0 Secondary Voltage Patterns

2.1 Set up your ignition oscilloscope or lab scope to view the secondary ignition patterns on your lab scope, with the engine warmed up and idling. (Use parade mode or individual mode on each different cylinder, depending on scope available.)

2.2 Record the average Firing Voltage (or “Step Up voltage) for each cylinder in the chart below. Some variation is normal, just pick the average. If you don’t understand what this is, review the resource information at the back of this worksheet.

2.3 Record the average Burn Time for each cylinder in the chart below.

        Are all these secondary ignition voltage readings normal? Yes ✓ No ____  Discuss what is happening in the pattern and what it is telling you about the ignition system.

It shows us that to create a good spark across the air gap in the plug, we need very high voltage in  very shot time

2.5 Do a Snap Acceleration (don’t damage the engine by revving too high or for too long) and record in the chart below how high the Firing Voltage (KV) went under Snap Acceleration.

Cyl 1	Cyl 2	Cyl 3	Cyl 4	Cyl 5	Cyl 6	Secondary Ignition
7KV	9KV	6.5KV	7.5KV	-	-	Firing Voltage (KV)
3ms	3ms	3ms	3ms	-	-	Burn Time (ms)
4kv	5kv	4kv	4kv	-	-	Snap Acceleration

2.6 Are all these Snap Acceleration secondary ignition voltage readings normal? Yes ✓ No ____ Discuss what is happening and what the pattern is telling you.

When we do a snap acceleration, the firing voltage slightly increased. This means that the higher rpm needs a higher firing voltage with short amount of burn time

2.7 Draw or photograph the Secondary Ignition lab scope pattern while idling from your scope into the box below. Do it carefully and show the detail you need to see for diagnosis.

2.8 If you can safely do this, (with the engine stopped), gently disconnect one spark plug wire, and short to the engine with a jumper wire. Which cylinder number did you short? 4

2.9 Start the engine and let it idle (for only a short time.) Record the new Firing Voltage and Burn Time for all the cylinders in the chart below.

Cyl 1	Cyl 2	Cyl 3	Cyl 4	Cyl 5	Cyl 6	Secondary Ignition (one cylinder grounded)
4.1KV	4KV	4.2KV	2KV	-	-	Firing Voltage (KV)
				-	-	Burn Time (ms)

2.10 Draw or photograph the shorted Secondary Ignition waveform you see now on your scope.

2.11 Discuss what is happening in the shorted ignition pattern and how the ignition pattern tells you what it is happening in the ignition system.

In this pattern, the firing voltage is very high for No. 4 plug  and burn time is very low but all other three plug having low firing voltage and high burn time.
Remove the ground wire and attach the spark plug wire back on the engine so it is normal again. Run the engine a bit to clear the spark plug

2.12 Remove the ground wire and attach the spark plug wire back on the engine so it is normal again. Run the engine a bit to clear the spark plug.

 So it is normal again. Run the engine a bit to clear the spark plug

2.13 Stop the engine and attach a spark tester to another spark plug wire. Start the engine and let it idle (for only a short time). Record the new Firing Voltage and Burn Time for all the cylinders in the chart below.

Cyl 1	Cyl 2	Cyl 3	Cyl 4	Cyl 5	Cyl 6	Secondary Ignition (Spark tester on one cylinder)
5kv	7kv	7kv	28	-	-	Firing Voltage (KV)
1.6ms	1.5ms	1.4ms	0.3ms	-	-	Burn Time (ms)

2.14 Draw or photograph the spark tester Secondary Ignition waveform you see now on your scope. Show the detail that is necessary for accurate diagnosis. Include time and voltages.

2.15 Stop the engine, remove the spark tester (be gentle), replace the spark plug wire, and run the engine to clear the spark plug. The engine should be back to normal now.

2.16 Discuss what happens to the ignition waveform when the spark tester is attached to the spark plug wire. What does it tell you about the ignition system. 

 The spark tester is at 20 kv (bigger spark gap) in #4 cylinder , the firing voltage increases to 6 kv and the burn time decreases to 1.3ms because there was a bigger spark gap.
 As a result, the firing voltage and burn time are related to the spark gap. If the spark gap is small the firing voltage will decrease and the burn time will increase. On the other hand, if spark gap is big the firing voltage will go up and the burn time will drop.

2.17 Remove the spark tester carefully, and put everything back together on the engine. Engine runs fine? ✓ yes, or ____ no. If any problems with vehicle, please tell your instructor.

                                           Dual trace

Using a dual trace (two channels A/B) oscilloscope capture the following

components and plot them against each other

The following sensors are used for

Lab Scope Referance:

Make Toyota Model 4A-FE
Signal Name Map & Fuel Injectors

A= Grounding / Dwell time

B= Voltage spike from collapsing magnetic feild
C= Stabilizing Voltage
D= Idle Voltage
E= Throttle Opening  (Increase in air pressure)
F= Throttle Shut (high vaccum)

Explain in detail how these two components relate each other

As the air pressure increases and the map voltage increases so the fuel injectors ground for a longer time (Dwell time) so fuel is being injected

A= Highest voltage induced from the magnets
B= Change in polarity
C= Neutral Point , no voltage induced

D= Dweel time

Explain in detail how these two components relate each other

As the peacks from the crank sensor become close or frequency increases fuel injectors ground more often because the RPM in the engine increases

Lab Scope

Make Toyota Model 4A-FE

Signal Name Primary ignition & fuel ignition

A= Dweel time/ Change time or primary coil
B= Firing KV when the coil is ungrounded
C= Dweel time of the fuel injector
D= Voltage returning to 12v after voltage spike

Explain in detail how these two components relate each other

The bigger the dweel time the primary coil kv builds up then fires , fuel injectors fire first

Lab Scope

Make Toyota Model 4A-FE

Signal Name Ignition voltage & ignition current

Draw the pattern below:

A= No current in coil
B= Max current build up in coil , when coil is ungrounded current drops to zero amps
C= Ground time / Dwell time of primary coil
D= Firing Kv

Explain in detail how these two components relate each other

When primary coils ground or driving dwell time , the current graduatly increase in the primary coil , until coil in ungrounded the current drops to zero and the firing kv is produced.

Explain in detail how one of the components would affect other

As current increases the magnetic feilds build up during coil dwell time

Explain the operation of the sensor or Actuator using the Graph:

(Use arrows at different points, and describe what happens there)

Draw the pattern below:

Explain the operation of the sensor or Actuator using the Graph:

(Use arrows at different points, and describe what happens there)

Lab Scope

Make Toyota Model 4A-FE

Signal Name Rpm/Crank Sensor

Volt/division/range 2v

Time/division/range 20ms

Draw the pattern below:

Explain the operation of the sensor or Actuator using the Graph:

(Use arrows at different points, and describe what happens there)

Explain the operation of the sensors or Actuators using the Graph:

(Use arrows at different points, and describe what happens there)

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