With Manufacturer's Scan Tool
Diesel Injection Timing Control Range, Checking
Checking the function of the injection timing control range is accomplished in function 04 (Basic settings). Using this procedure, the cold start injector is pulsed so that the range of values for the advanced and retarded positions of the injection timing device can be read in display field 3.
NOTE: Only gold-plated contacts must be used when repairing terminals in the connector to the injection pump.
Special tools, workshop equipment, testers, measuring instruments and auxiliary items required
- VAG 1551/1552 Scan tool with adapter cable VAG 1551/3
- Test box VAG 1598/22
- Digital multimeter US1119 (Fluke 83 or equivalent)
- Adapter set VAG 1594
- Wiring diagram
Test sequence
- Connect VAG 1551/1552 (Connecting scan tool and selecting engine electronics control module). Testing and Inspection
- Run engine at idle speed and press buttons -0- and -1 - to select "Engine electronics" address word 01.
Indicated on display
Rapid data transfer HELP
Select function XX
- Press buttons -0- and -4- to select "Basic setting" function 04 and confirm entry with -Q- button.
Indicated on display
Basic setting HELP
Input display group number XXX
- Press buttons -0-, -0- and -4- to select "Display group number 4" and confirm entry with -Q- button.
Indicated on display
System in basic setting 4 ->
900 rpm adv. 7.9 ° BTDC 47 %
- Specified value in display field: 3: 7.0 to 9.0° BTDC
After approx. 10 seconds the spray adjuster is moved to the retarded (late) position.
Indicated on display
System in basic setting 4 ->
900 rpm ret. 4.4° BTDC 32%
- Specified value in display field 3: 3.0 to 5.0° BTDC
- Press the -> button
- Press buttons -0- and -6- to select "End output" function 96 and confirm entry with -Q- button.
- Switch ignition off.
If the specifications are not obtained:
- Check cold start injector as follows:
- Disconnect the 10-pin connector for the cold start injector (connector to injection pump) (arrow).
- Measure resistance between connector terminals 9 + 10.
- Specification: 12.0 to 20.0 ohms
If the specification is not obtained:
- Replace Cold Start Injector -N108- See "Injection Pump, Servicing", item 17. Procedures
- Check DTC memory and, if necessary, repair any malfunctions and then erase. Testing and Inspection
- Read readiness code. Testing and Inspection
If the DTC memory has been erased or the engine control module was disconnected from permanent battery positive (B +), the readiness code must be generated again. Testing and Inspection
If the specification is obtained:
- Remove wiper arms and plenum cover.
- Connect test box VAG 1598/22 to control module wiring harness.
- Check wiring between test box and 10-pin connector for open circuit according to wiring diagram.
Terminal 9 + socket 79
Terminal 10 + socket 2
Terminal 10 + socket 28
- Wire resistance: max. 1.5 ohms
- Check wires for short to one another, to vehicle earth and to battery positive.
- Specification: Infinity ohms
If wiring and the resistance measurement values are OK:
- Replace engine control module. Service and Repair