Code result
U0013
Medium Speed CAN Communication Bus (-) Low
Moderate severity
What it means
The CAN-Low signal of the medium-speed bus is shorted to ground. Comfort and body modules can no longer exchange messages and trigger several user-visible faults at once (windows, locking, lighting).
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
CAN-Low shorted to ground
highOne of the most commonly reported causes for this code — check this first.
Water ingress in door connector
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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