Code result
U0002
High Speed CAN Communication Bus Performance
Moderate severity
What it means
The high-speed CAN bus is functional but performance is degraded — frame errors, bit errors or excessive bus load have been detected. Communication may be intermittent rather than completely lost, leading to sporadic warning lamps.
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
Corrosion or poor contact in CAN connectors
highOne of the most commonly reported causes for this code — check this first.
Electromagnetic interference (aftermarket electronics)
mediumA plausible cause — test and verify before replacing parts.
One module sending malformed frames
mediumA plausible cause — test and verify before replacing parts.
Related help
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