Code result
U0008
High Speed CAN Communication Bus High
High severity
What it means
The CAN-Low signal is held above its valid range, typically because of a short to battery voltage on the CAN-L wire. Bus communication is lost for every node sharing this segment.
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-Low shorted to battery voltage
highOne of the most commonly reported causes for this code — check this first.
Chafed harness against power wire
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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