Main Instrument Unit

Vehicle speed signal faulty





Fault symptoms
Speedometer in max. position, 250 km/h.

Condition
Speed information from TC/ABS control module exceeds 270 km/h.

Diagnostic help
The current speed information can be read with the diagnostic tool.
The speedometer can also be activated with the diagnostic tool.

When the speedometer is activated with the diagnostic tool, this value will not be sent to the bus.

Checking the wiring harness
Jiggle the wiring harness at several points and in different directions to detect intermittent breaks and short-circuits in the leads.
Observe the multimeter, test lamp or diagnostic tool during the test.