audi Workshop Repair Guides

Audi Workshop Service and Repair Manuals

Testing data exchange between engine/ABS/gearbox control unit, dash panel insert > < Testing crash signal
Motronic injection and ignition system (6 cyl. turbo)
Checking auxiliary signals
Testing rough-road detection signal from ABS/EDS control unit

Notes:

  • ◆ If the ABS/EDS control unit detects a spinning wheel, the ABS/EDS control unit generates the rough-road signal.
    If the engine control unit detects the rough-road signal, the misfire detection is switched off in engine control unit.
  • ◆ The rough-road signal must only be tested if the fault "18014 (P1606) Rough-road detection/engine specified torque ABS CU, electrical fault in circuit" is stored.
    The possible additional fault "Misfire" is then a sequential fault and can be ignored.
  • ◆ The wiring and rough-road signal are monitored by the engine control unit

Test conditions

  • ● Control unit code OK .

Test sequence

  • ‒ Switch ignition off.
  • ‒ Connect the V.A.G 1598/31 test box to wiring harness leading to engine control unit; the engine control unit should not be connected => Page 24-22.
  • ‒ Check wiring from socket 74 on test box to ABS control unit for short circuit or open circuit according to current flow diagram.

=> Current Flow Diagrams, Electrical Fault-Finding and Fitting Locations

If no wiring fault is detected:

  • ‒ Replace ABS control unit

If fault is re-displayed after replacing ABS control unit:

  • ‒ Fit a new engine control unit => Page 24-26.

Testing data exchange between engine/ABS/gearbox control unit, dash panel insert > < Testing crash signal