U0108
Lost Communication With Alternative Fuel Control Module
The ECU has lost CAN communication with the alternative fuel control module (CNG/LPG/H2 systems). Either the module is not responding or the bus path is broken.
The ECU has lost CAN communication with the alternative fuel control module (CNG/LPG/H2 systems). Either the module is not responding or the bus path is broken.
Common causes
- high
Module unpowered or fuse blown
One of the most commonly reported causes for this code — check this first.
Typical part cost: $60-1320
- medium
CAN wiring to module broken
A plausible cause — test and verify before replacing parts.
Typical part cost: $60-1320
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First things to check
- 1Confirm the code with a scan tool and check for additional related codes.
- 2Inspect the relevant sensors, wiring, and connectors for damage or corrosion.
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Related codes
See related trouble codes
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Frequently asked questions
What does U0108 mean?
U0108 means "Lost Communication With Alternative Fuel Control Module". It is a generic OBD-II code that points to a fault in the network / communication.
What are the most common causes of U0108?
module unpowered or fuse blown; can wiring to module broken; gateway module routing can messages incorrectly — these are the most commonly reported causes. Verify with a proper diagnosis before replacing parts, or use the Wrenchify app for a vehicle-specific diagnosis.
Can I keep driving with this code?
The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical. Use the Wrenchify app for a full diagnosis specific to your vehicle.
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