U0001
High Speed CAN Communication Bus
OBD-II
Wiring / network
What it means
Fault on the high-speed CAN bus — wiring, a shorted module, or a terminating resistor.
Seeing U0001?
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U0002
High Speed CAN Communication Bus Performance
Wiring / networkHigh
U0003
High Speed CAN Communication Bus (+) Open
Wiring / networkHigh
U0004
High Speed CAN Communication Bus (+) Low
Wiring / networkHigh
U0005
High Speed CAN Communication Bus (+) High
Wiring / networkHigh
U0006
High Speed CAN Communication Bus (-) Open
Wiring / networkHigh
U0007
High Speed CAN Communication Bus (-) Low
Wiring / networkHigh
U0008
High Speed CAN Communication Bus (-) High
Wiring / networkHigh
U0009
High Speed CAN Communication Bus (-) Shorted To Bus (+)
Wiring / networkHigh
General reference only — what a code means can vary by make and model. Confirm with a qualified technician.