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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

Normal Operation
The PCM communicates with the scan tool through the high speed controller area network (HS-CAN). Circuits VDB04 (WH/BU) (HS-CAN +) and VDB05 (WH) (HS-CAN -) provide the network connection to the PCM. The PCM shares the HS-CAN with the transmission control module (TCM), the ABS module, the restraints control module (RCM), the 4X4 control module (if equipped), the air suspension module (if equipped) and the instrument cluster (IC).

This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- PCM


A1-A3:






A3-A4:






A5-A6: