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Test T: The Transmission Control Module (TCM) Does Not Respond To The Scan Tool

PINPOINT TEST T: THE TRANSMISSION CONTROL MODULE (TCM) DOES NOT RESPOND TO THE SCAN TOOL


T1-T4:






Normal Operation
The TCM 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 TCM. The TCM shares the HS-CAN network with the powertrain control module (PCM), the traction battery control module (TBCM), the anti-lock brake system (ABS) module, the power steering control (PSC) module, the four wheel drive (4WD) control module, and the instrument cluster. Voltage for the TCM is provided by circuits 69 (RD/LG) and 1865 (WH/OG). Ground is provided by circuits 57 (BK).

Possible Causes
- Fuse
- Circuit 57 (BK) open
- Circuit 69 (RD/LG) open
- Circuit 1865 (WH/OG) open
- Circuit 1908 (WH) open (HS-CAN +)
- Circuit 1909 (BK) open (HS-CAN -)
- TCM