With Manufacturer's Scan Tool

CAN-Bus, checking

When a CAN-Bus malfunction is indicated during a check of DTC memory of the Engine Control Module (ECM), refer to the following test to eliminate the malfunction.


NOTE:
- The information exchange occurs between the Engine Control Module (ECM) and the Transmission Control Module (TCM) via a CAN-Bus.
- All signals are carried by 2 wires between the ECM and the TCM.

Required special tools and test equipment
- VAG 1551 or VAG 1552 Scan Tool (ST) with VAG 15551/3 adapter cable
- VAG 1598/22 test box
- VW 1594 connector test kit
- Wiring diagrams

Checking

- Check DTC memory of Transmission Control Module (TCM).

If a DTC regarding the CAN-Bus wire is also stored in the TCM:
- Switch ignition off.






- Connect VAG 1598/22 test box to ECM harness connector. Connecting VAG 1598/22 Test Box
- Check wires from terminal 29 and terminal 41 of test box to transmission control module for open or short circuit per wiring diagram.

If wiring is OK:
- Replace Transmission Control Module (TCM) and Engine Control Module (ECM) as necessary and in sequence.