P1604

Test 1:

SYMPTOM
P1604-PCM INTERNAL DUAL-PORT RAM READ/WRITE INTEGRITY FAILURE

TEST NOTE
This symptom is diagnosed using the test P1603-PCM INTERNAL DUAL-PORT RAM COMMUNICATION.

WHEN MONITORED
During cold start.

SET CONDITION
Compares shut down time to coolant temperature.

POSSIBLE CAUSES
- Fused ignition switch output (Off-Run-Start)
- PCM internal failure