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Test J

PINPOINT TEST J: NO POWERTRAIN CONTROL MODULE (PCM) STANDARD CORPORATE PROTOCOL (SCP) NETWORK COMMUNICATION


Test J1-J3:






Normal Operation
The PCM communicates with the modules through the standard corporate protocol (SCP) communications network. Circuits 4-RE8 (GY) and 5-RE8 (BU) receive and transmit data from the PCM to the modules through the interior auxiliary junction box (AJB). Degraded SCP performance occurs if one bus line is open, shorted to ground or voltage, or if one but not all termination resistors are lost.

Possible Causes
- circuit 4-RE8 (GY) open
- circuit 5-RE8 (BU) open
- PCM C175b
- PCM
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