P1897-LEVEL 1 RPM BUS UNLOCK

For a complete wiring diagram Refer to Section 8W.


  • When Monitored:

    Engine running.

  • Set Condition:

    When the PCM recognizes an internal failure to communicate with the FCM or the CMP and CKP Sensor count periods are too short. One trip fault. ETC light is flashing.


Possible Causes
  
PCM
  

Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING).



Diagnostic Test

1.PCM

NOTE: Diagnose any CMP or CKP Sensor faults before continuing. Check for intermittent loose CMP or CKP connections.



The Powertrain Control Module is reporting internal errors, view repair to continue.

Repair