Code result
U0073
Control Module Communication Bus \"A\" Off
High severity
What it means
A control module has detected that the communication bus is non-functional and has shut its bus interface off. Affects multiple modules at once because none can communicate; on most vehicles the dashboard lights up with several warning lamps simultaneously.
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
CAN line shorted to supply or ground
highOne of the most commonly reported causes for this code — check this first.
Terminating resistor failed
mediumA plausible cause — test and verify before replacing parts.
One failing module pulling the bus down
mediumA plausible cause — test and verify before replacing parts.
Related help
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