Network
generic / SAE
U0138
Lost Communication with All Terrain Control Module
The terrain mode / 4WD mode controller has dropped off the bus. Off-road and traction modes can no longer be selected; vehicle defaults to standard 2WD/AWD behaviour.
SystemNetwork
Typegeneric / SAE
GroupU0
Range / number1 / 38
Possible causes
- Module unpowered high
- Gateway module routing CAN messages incorrectly low
- CAN terminating resistor (120 Ω) drifted out of spec low
Symptoms
- Multiple warning lights may illuminate
- Affected modules may go into limp mode or shut down
- Specific functions inoperative depending on module
- Diagnostic tools may show communication faults
Inspection / repair
- Difficulty: hard
- DIY: shop recommended
- Estimated cost: 60–600 €
- Estimated time: 0.5–3 h
- Component: terrain control module
- Component: can bus wiring
- MIL / check engine light
Sources
References
sae:J2012