Code result
U0028
Vehicle Communication Bus A
Moderate severity
What it means
Generic fault on vehicle communication bus A. The controller flags an unspecified electrical or protocol fault on this bus segment that does not match the more specific U0xxx subcodes.
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
Intermittent CAN wiring fault
highOne of the most commonly reported causes for this code — check this first.
Marginal node corrupting traffic
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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