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Test A





Pinpoint Test A: No Communication With The 4x4 Module (PCM)

Normal Operation

In order for the 4x4 module (PCM) to communicate with the scan tool, the operating voltage required to supply the 4WD module is in a range between 9 and 16 volts. Voltage is supplied by circuit 729 (RD/WH) and circuit 994 (WH).

Possible Causes
- CAN communication
- scan tool
- battery junction box (BJB) fuse 18 (20A)
- central junction box (CJB) fuse 24 (15A)
- power supply
- circuit 729 (RD/WH)
- circuit 994 (WH)
- ground circuits:
- circuit 570a (BK/WH)
- circuit 570b (BK/WH)
- 570c (BK/WH)
- 4x4 module (PCM)
- charging system

Caution: Use the Flex Probe Kit for all test connections to prevent damage to the wiring terminals. Do not use standard multimeter probes.

Pinpoint Test A1 - A4:





Pinpoint Test A5 & A6: