Code result
U0011
Medium Speed CAN Communication Bus Performance
Moderate severity
What it means
The medium-speed CAN bus is operating but with degraded performance — frame errors or excessive error counters. Comfort and infotainment functions may operate intermittently.
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 in body harness connectors
highOne of the most commonly reported causes for this code — check this first.
One module sending malformed frames
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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