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Test F: The Air Suspension Module Does Not Respond To The Scan Tool

PINPOINT TEST F: THE AIR SUSPENSION MODULE DOES NOT RESPOND TO THE SCAN TOOL


F1-F2:






F3-F4:






Normal Operation
The air suspension module 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 air suspension module. The air suspension module shares the HS-CAN with powertrain control module (PCM), the transmission control module (TCM), the anti-lock brake system (ABS) module, the restraints control module (RCM), the four wheel drive (4WD) control module (if equipped) and the instrument cluster. Voltage for the air suspension module is provided by circuits CBB65 (WH/OG) and SBB47 (WH/RD). Circuits GD120 (BK/GN) and GD133 (BK) provide ground.

DTC U0122 - sets in a module which had attempted to communicate with the air suspension module and failed.

Possible Causes
- Fuse
- Circuit CBB65 (WH/OG) open
- Circuit SBB47 (WH/RD) open
- Circuit GD120 (BK/GN) open
- Circuit GD133 (BK) open
- Circuit VDB04 (WH/BU) open (HS-CAN +)
- Circuit VDB05 (WH) open (HS-CAN -)
- Air suspension module