DS - Testing Notes
NOTE: You should enter this Pinpoint Test only when you have been directed here from Quick Test.REMEMBER
To prevent the replacement of good components, be aware that the following non-EEC areas may be at fault.
- Vehicle Speed Control system
- Rear Anti-Lock Brake system
- Instrumentation system
This Pinpoint Test is intended to diagnose only the following:
- PSOM output to the processor
- Harness circuits: PSOM(+), PSOM(-)
- Processor assembly
DESCRIPTION
The Programmable Speedometer/Odometer (PSOM) receives inputs from the Rear Anti-Lock Brake System (RABS) Speed Sensor, which is mounted on the rear axle differential. The PSOM takes the input signal information to the Speed Control module and the EEC-IV processor.