audi Workshop Repair Guides

Audi Workshop Service and Repair Manuals

Testing signals to and from dash panel insert > < Testing signals from and to ABS control unit
TDI®injection and glow plug system (4-cyl. unit injector)
Testing signals from and to ABS control unit
Testing signal wire (CAN bus) between engine control unit and ABS control unit

The engine control unit and the ABS control unit are connected to each other via a CAN bus. The CAN bus consists of two signal wires which are used to transmit information (e.g. engine torque, engine speed).

Test sequence

  • ‒ Connect test box V.A.G 1598/31 to wiring harness for engine control unit.Do notconnect to the engine control unit itself:
    • ‒ Connecting test box to engine control unit without protective housing=>Page 23-49.
    • ‒ Connecting test box to engine control unit with protective housing=>Page 23-51.
  • ‒ Test for open circuit and short to earth or positive in the following wiring connections:

Test box
V.A.G 1598/31
Socket

ABS control unit
-J104
Contact

6
7

=> Current flow diagrams, Electrical fault-finding and Fitting locations binder

  • ‒ Rectify any open/short circuit as necessary.

Testing signals to and from dash panel insert > < Testing signals from and to ABS control unit