Engine Speed Signal, Checking

Additional signals, checking
RPM signal, checking
Function
The engine speed (RPM) signal is output via contact 27 on the engine control module. The signal is required, among others, by the automatic transmission control module to calculate the gear change points and for rev counter in the instrument cluster.


Special tools, testers and auxiliary items required
^ Test box V.A.G1598/31
^ Adapter set V.A.G. 1594
^ Multimeter V.A.G. 1526 or Multimeter V.A.G. 1715
^ Wiring diagram

Work sequence
- Switch off ignition.
- Remove windshield wiper arms and cover for plenum chamber





- Unlock and separate connector on engine control module.
- Connect test box V.A.G.1598/31 to control module wiring harness.
- Check wiring for open circuit between test box socket 27 and instrument cluster for open or short circuit referring to wiring diagram. Wire resistance- max. 1.5 0hms. Refer to Wiring Diagrams,