Component Tests

ABS control module with ABS/EDL

NOTES:
- Misfires can result in malfunctions such as "Combustion misfire" being recorded in DTC memory due to road wheel malfunctions.
- If the ABS control module recognizes a free turning wheel, it generates a rough road signal.
- If the Engine Control Module (ECM) recognizes the rough road signal, misfire recognition is switched off in the ECM.
- The rough road signal is created to check whether DTC 1801, "Rough Road Spec Engine Torque ABS-SG Electrical Malfunction" is stored in DTC memory. The "Combustion misfire" malfunction results from this signal and can be ignored.
- The rough road signal is monitored by the ECM.

Checking requirement
- Control module coding OK.

- Switch ignition OFF.
- Connect VAG 1598/19 test box to ECM harness connector.
- Check signal wire for open or short circuit between ECM and ABS control module, using wiring diagram.
- Find and eliminate open or short circuit; repair as necessary. If wiring is OK:
- Replace ABS control module.

If the ABS control module is OK, but the malfunction is still occurring:
- Replace ECM.

ABS control module with ABS/EDL/ASR

NOTES:
- The torque signal is monitored by the "Automatic Traction Control" Control Module and by the ECM.
- Vehicles with automatic traction control (ASR) can be recognized by the ASR indicator light in the instrument cluster or by control module identification displayed during the ABS On Board Diagnostic program sequence

Checking requirement
- Control module coding OK, Engine Control Module.