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Home >> Ford >> 2008 >> F 450 4WD Super Duty V10-6.8L >> Repair and Diagnosis >> Powertrain Management >> Computers and Control Systems >> Information Bus >> Testing and Inspection >> Pinpoint Tests >> Test A: The Powertrain Control Module (PCM) Does Not Respond To The Scan Tool
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Test A: The Powertrain Control Module (PCM) Does Not Respond To The Scan Tool

PINPOINT TEST A: THE POWERTRAIN CONTROL MODULE (PCM) DOES NOT RESPOND TO THE SCAN TOOL

Normal Operation
The PCM 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 PCM. The PCM shares the HS-CAN network with the ABS module, trailer brake control (TBC) module (if equipped), restraints control module (RCM), supplemental heater control module (diesel engine only, if equipped), transmission control module (TCM) (diesel engine only, if equipped), variable geometry turbocharger (VGT) actuator (diesel engine only) and the instrument cluster. Voltage for the PCM is provided by circuits CBB76 (BU/BN) and SBB36 (GN/RD). Circuit GD113 (BK/YE) provides ground.

Possible Causes
- Circuit VDB04 (WH/BU) open (HS-CAN +)
- Circuit VDB05 (WH) open (HS-CAN -)
- PCM


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