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 CausesPCMAlways perform the Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING).1. PCMDiagnose 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.RepairReplace and program the Powertrain Control Module per Service Information.Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE).