DS1 - Check PSOM Resistance
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Continuous Memory Diagnostic Trouble Code (DTC) 29 indicates that during the last 80 warm-up cycles, the Powertrain Control Module (PCM) detected an error in the Programmable Speedometer/Odometer Module (PSOM) output signal. DTC 452 indicates the PCM detected an error in the PSOM output signal during the last 40 warm-up cycles. Possible Causes:
- Damaged Rear Anti-Lock Brake System (RABS).
- Damaged PSOM.
- Damaged harness circuits.
- Damaged PCM.
- Key "OFF".
- Disconnect PCM. Inspect for damaged or pushed out pins, corrosion, loose wires, etc. Service as necessary.
- Install breakout box, leave PCM disconnected.
- Measure resistance between test pin 3 and test pin 6 at the breakout box.
- Is resistance between 21,000 and 55,000 ohms?
Yes -- Go to DS4. DS4 - Check RABS Sensor Resistance
No -- Go to DS2. DS2 - Check Continuity of the Harness Circuit