F 250 2WD Super Duty V8-5.4L (2008)
F2-F4
Test G: The Transmission Control Module (TCM) Does Not Respond To The Scan Tool
PINPOINT TEST G: THE TRANSMISSION CONTROL MODULE (TCM) DOES NOT RESPOND TO THE SCAN TOOL
Normal Operation
The transmission control module (TCM) is used on automatic transmission equipped diesel engine vehicles only. 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 HS-CAN network connection to the TCM. The TCM shares the HS-CAN network with the PCM, the ABS module, the trailer brake control (TBC)
module (if equipped), the variable geometry turbocharger (VGT) actuator, the instrument cluster, the supplemental heater control module (if
equipped) and the restraints control module (RCM). Voltage for the TCM is provided by circuits CBB72 (GN/VT) and SBB37 (GY/RD). Circuit
GD120 (BK/GN) provides ground.