Test A: The Powertrain Control Module(PCM) Does Not Respond To The Scan Tool, or No High Speed Controller Area Network (HS-CAN)

PINPOINT TEST A: THE POWERTRAIN CONTROL MODULE (PCM) DOES NOT RESPOND TO THE SCAN TOOL, OR NO HIGH SPEED CONTROLLER AREA NETWORK (HS-CAN) COMMUNICATION

A1-A2:

A3-A4:

A5-A8:

A8-A10:

A10-A12:

A12-A14:

A14-A16:

A16-A18:

A18-A20:

A20-A22:

A23-A26:

A27:

Normal Operation
The PCM communicates with the scan tool through the high speed controller area network (HS-CAN). Circuits 1908 (WH) (HS-CAN +) and 1909 (BK) (HS-CAN -) provide the network connection to the PCM. The PCM shares the HS-CAN network with the transmission control module (TCM), the anti-lock brake system (ABS) module, the restraints control module (RCM), the differential electronic module (DEM) and the instrument cluster. Voltage and ground for the PCM is provided by redundant circuits. Circuit 361 (RD) provides voltage, and circuit 1205 (BK) provides ground.

DTC U1900 (ABS) - sets when the HS-CAN bus performance is compromised.

DTC U1900 (RCM) - sets when the HS-CAN bus performance is compromised.

DTC U1900 (instrument cluster) - sets when the HS-CAN bus performance is compromised.

Possible Causes
- Fuse
- Circuit 116 (RD/BK) open
- Circuit 361 (RD) open
- Circuit 1205 (BK) open
- Circuit 1908 (WH) open, short to ground or voltage (HS-CAN +)
- Circuit 1909 (BK) open, short to ground or voltage (HS-CAN -)
- Circuit 1908 (WH) (HS-CAN +) and circuit 1909 (BK) (HS-CAN -) shorted together
- ABS module
- DEM
- PCM
- RCM
- TCM
- Instrument cluster