Test Point 28

TEST POINT 28
CAN Bus Fault

DTC 101

Fault Effect: Reduced driving program.

Notes:
- The Tiptronic control module is connected with the DmE control module via a data lead (CAN bus).
- Never pull off or push on the control module connector with the ignition switched on.

If the DmE control module connector is pulled off with the ignition switched on, for example, the onboard diagnostic system can detect a "CAN : bus or DPRAm" fault under certain circumstances.

1. Read out the DmE fault memory. If the fault "CAN : bus or DPRAm fault" is stored, check the wiring from the Tiptronic control module to the DmE control module

2. Check the wiring from Tiptronic control module pin 85 (or 86) to DmE control module pin 85 (or 86) for continuity, short to ground and short to B+.

Note:
If the wiring is OK and fault is stored in one control module only, the fault can lie in another control module.