Computers and Control Systems: Service and Repair

The Diesel Turbo Direct Injection (TDI) system control module is equipped with a Diagnostic Trouble Code (DTC) memory.

Before starting repairs, adjustments and troubleshooting:
- Check DTC memory for possibility of stored Diagnostic Trouble Codes (DTCs),
- Perform Output Diagnostic Test Mode, at "Diagnosis With Scan Tool, Address Word 01". Testing and Inspection

NOTE: When performing checking and adjusting operations, the Engine Control Module (ECM) may recognize and store malfunctions.

For this reason; after completing all checking and adjusting operations you must:
- Erase the DTC memory
Then
- Recreate the readiness code





Components A to D are not shown on the illustration.
A. Brake pedal switch F47 and brake light switch F
- Combined into one assembly in footwell on brake pedal
B. Throttle Position sensor G79
- In footwell on accelerator pedal
C. Clutch vacuum vent valve switch F36
- In footwell on clutch pedal
D. Barometric Pressure sensor F96
- From 08.94: Internally installed in TDI system Engine Control Module J248

1. Diesel Turbo-Direct Injection system Engine Control Module (ECM) J248
- With Manifold Absolute Pressure sensor G71
- With Barometric Pressure sensor F96
2. Fuel cut-off valve N109
3. Fuel injector with Needle Lift sensor G80
4. Engine Coolant Temperature sensor G62
5. Connector
- for Needle Lift sensor G80
6. Coolant glow plug relay J325
7 Wastegate Bypass Regulator valve N75
8. Intake Air Temperature sensor G72
9. Connector
- for Engine Speed sensor G28
10. Harness connector
- For Fuel Temperature sensor G81
- For Quantity Adjuster N146
- For Modulating Piston Displacement sensor G149
11. Connector
- For Fuel cut-off valve N109
- For Cold start injector N108
12. Injection pump Quantity Adjuster
- With Fuel Temperature sensor
- With Quantity Adjuster N146
- With Modulating Piston Displacement sensor G149
13. EGR Vacuum Regulator solenoid valve N18
14. Mass Air Flow sensor G70