U0028

Vehicle Communication Bus A

Moderate severity

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.

Common causes

Intermittent CAN wiring fault
One of the most commonly reported causes for this code — check this first.
high
Typical part cost: $90-770
Marginal node corrupting traffic
A plausible cause — test and verify before replacing parts.
medium
Typical part cost: $90-770
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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

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Frequently asked questions

What does U0028 mean?

U0028 means "Vehicle Communication Bus A". It is a generic OBD-II code that points to a fault in the network / communication.

What are the most common causes of U0028?

intermittent can wiring fault; marginal node corrupting traffic; 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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