WS5 Scan Tool Diagnostics

 NISSAN   Pualsar  1991
(Course: using a Scan Tool that communicates to the engine you want to test.)
Warning: Be careful working around engines and exercise caution to avoid injury.
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 idle. 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 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.

Engine Load(how much air comes in)
MAF  1 v
Engine RPM
RPM  825 RPM
Throttle angle
TPS(idling)  0.48 v
Engine coolant temperature
ECT  93 ℃
Fuel Injection Opening pulse
2.4 ms (idling)
Vehicle Speed
0  km/h
Idle control
IACV  52 %
Ignition timing
15 BTDC
* The O2 Sensor did not respond with any voltages due to the O2 sensor was damaged with its visual inspection(bending damage) 

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) If there are no codes listed, put “none”.

NONE

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.

11 CAM Position Sensor  :  The engine is not running.
12 MAF : Idling rough and the engine is turned off.
21 Ignition Primary : No engine starting.

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:

Idle  RPM  560~700 RPM
Idle Air Control Valve  IACV  30%
Injection Pulse  2.9 ms
MAF 0 v

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:

The vacuum sensor(MAF) was disconnected. As a result, the engine idle was rough and the engine was turned off. When I checked the parameter identification of the scan tool, it was changed, such as RPM, IACV, Injection Pulse and MAF sensor signal. 

7 Repair fault

7.1 Plug back in the connector, or repair problem found

7.2 Describe what you did:

I have reconnected the vacuum sensor connector and then restarted the engine. The engine runs well with out any problems.

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
The engine was recovered normal conditionsIdle RPM  800 RPM
Idle Air Control Valve IACV  52%
Injection Pulse 2.4 ms
MAF 0.98 v

9 Clear Codes

Describe what you did to clear codes:

I made a disconnection of the negative terminal or the engine main fuse for 30 seconds.
From the scan tool, I choose the clear codes of scan tool menu then I have deleted all fault codes.

10 Recheck for codes and record codes in system now:

When I recheck the codes from selecting scan menu, there were no trouble codes on the screen.

11 Discuss the importance live data when fault finding

It shows the state of the sensors and actuators from the live data values, so I can find the problems easily.

12 Explain the need for parameters when checking live data

when the fault is resolved, the live data will be rechecked with its parameters then the data should be compared to fault data.

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

I can find the fault easily and although the vehicle is old or new, I can also check the state of a vehicle with various information.