Code result
U0045
Vehicle Communication Bus B
High severity
What it means
The two lines of differential bus B are shorted together. A communication loss with this module breaks any function relying on its data — diagnostic tools may show 'no response' and dependent modules can fall into limp mode.
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
Bus lines shorted together
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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