Code result
U0037
Vehicle Communication Bus B
High severity
What it means
Generic fault on vehicle communication bus B (second physical bus, e.g. body CAN, comfort CAN, or LIN). One or more nodes cannot communicate.
Is it safe to drive?
No — stop driving
This code can put the vehicle into limp or reduced-power mode. Avoid extended driving and have the vehicle diagnosed promptly.
Most likely causes
Wiring or node fault on bus B
highOne of the most commonly reported causes for this code — check this first.
Gateway module routing CAN messages incorrectly
lowLess common, but worth ruling out after the more likely causes.
CAN terminating resistor (120 Ω) drifted out of spec
lowLess common, but worth ruling out after the more likely causes.
Related help
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