Troubleshooting and Testing Requirements

Electrical testing
- If the On Board Diagnostic (OBD) sequence does not provide any indication of the source of the malfunction, work through all of the electrical test steps.
- If the OBD sequence identifies the source of the malfunction, only carry out the test steps recommended in the DTC table (specific testing).

Test conditions
- "Automatic Test Sequence" carried out to establish that any malfunctions stored in Transmission Control Module (TCM) and Motronic Engine Control Module (ECM) only affect ABS/EDL.

Automatic test sequence:
- Connect VAG1551 scan tool and (with ignition switched on) insert "Automatic Test Sequence".
- After completing electrical testing, check and erase DTC memories of Transmission Control Module (TCM) and Motronic Engine Control Module (ECM).

CAUTION: Damage to the system may be caused if electrical testing is not conducted property. No terminals may be bridged, except for those listed in the test table.





- Multi-pin harness connector for ABS control module -J104- in proper condition, with no bent, broken or corroded terminals.

- Replace any damaged terminals using VAS1 978 wiring repair kit.

Note: The instructions supplied with the VAS 1978 wiring repair kit do not permit repairs to the shielded wiring of the ABS/EDL and related systems.

- Ignition and electrical consumers switched off before beginning testing (headlights, lighting, fan, etc.)

Required special tools and test equipment
- Test box VAG 1598
- Adapter VAG 1598/27
- Connector test kit VAG 1594
- Multimeter US 1119 (Fluke(R) 83 or equivalent)

Connecting VAG1598 test box with VAG1598/27 adapter and checking ABS/EDL/ASR
- Switch ignition off.
- Connect VAG1598/27 adapter to VAG1598 test box.
- Disconnect multi-pin connector from ABS control module -J104-, and connect VAG1598/27 adapter and VAG1598 test box to multi-pin connector on ABS/EDL wiring harness.
The socket designations on the VAG1598 test box are identical to the terminal designations on the ABS control module -J104- and on the wiring harness connector.
Refer to Diagrams/Diagnostic Aids.





Terminal assignments for multi-pin ABS control module -J104- harness connector

Note: All terminals not listed are currently not assigned and must not be connected to other components.