Code result
U0108
Lost Communication With Alternative Fuel Control Module
Moderate severity
What it means
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.
Is it safe to drive?
Use caution
The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical.
Most likely causes
Module unpowered or fuse blown
highOne of the most commonly reported causes for this code — check this first.
CAN wiring to module broken
mediumA plausible cause — test and verify before replacing parts.
Gateway module routing CAN messages incorrectly
lowLess common, but worth ruling out after the more likely causes.
Related help
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