Operation CHARM: Car repair manuals for everyone.

Test B: The Transmission Control Module (TCM) Does Not Respond to the Scan Tool

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


B1-B2:






B3-B4:






Normal Operation
The 6R60 transmission utilizes a TCM to control transmission functions. The TCM 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 TCM. The TCM shares the HS-CAN network with the powertrain control module (PCM), the anti-lock brake system (ABS) module, the restraints control module (RCM), the four wheel drive (4WD) control module (if equipped), the occupant classification sensor module and the instrument cluster. Voltage for the TCM is provided by circuits SBB27 (BU/RD) and CE517 (BU/GN). Circuit GD113 (BK/YE) provides ground.

Possible Causes
- Fuse
- Circuit CE517 (BU/GN) open
- Circuit GD113 (BK/YE) open
- Circuit SBB27 (BU/RD) open
- Circuit VDB04 (WH/BU) open (HS-CAN +)
- Circuit VDB05 (WH) open (HS-CAN -)
- TCM