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Test A: The Powertrain Control Module (PCM) Does Not Respond to the Scan Tool

PINPOINT TEST A: THE POWERTRAIN CONTROL MODULE (PCM) DOES NOT RESPOND TO THE SCAN TOOL


A1-A2:






A3-A4:






Normal Operation
The PCM communicates with the scan tool through the high speed controller area network (HS-CAN). Circuits 1827 (WH/LG) (HS-CAN +) and 1828 (PK/LG) (HS-CAN -) provide the network connection to the PCM. The PCM shares the HS-CAN network with the anti-lock brake system (ABS) module and the instrument cluster.

Possible Causes
- Circuit 1827 (WH/LG) open (HS-CAN +)
- Circuit 1828 (PK/LG) open (HS-CAN -)
- PCM