Code result
U0077
Vehicle Communication Bus B Off
Moderate severity
What it means
A controller on bus B has reached its transmit error limit and shut its transceiver off. All traffic on this segment stops until the cause is removed.
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
Persistent wiring 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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