U0009critical severityNetwork
High Speed CAN Communication Bus Shorted Together
on 2011 Hyundai Tucson 2.0L I4 · AWD
What this code means
CAN H and CAN L wires are shorted to each other, preventing differential signaling on the bus.
Symptoms
- Complete CAN bus failure
- No communication with any module on bus
- Vehicle may not start
Common causes
- CAN H and CAN L wires shorted together
- Connector pin damage
- Crushed wiring harness
- Rodent damage to wiring
Diagnostic steps
- Measure resistance between CAN H and CAN L (should be ~60 ohms with termination)
- Inspect wiring for physical damage
- Check connectors for bent pins
- Disconnect modules and measure resistance at each segment
Repair notes
Locate the short between CAN H and CAN L. Common in door jambs and under-dash wiring.
Other Network codes on this vehicle
U0001
High Speed CAN Communication Bus
U0001
High Speed CAN Communication Bus
U0002
High Speed CAN Communication Bus Performance
U0002
High Speed CAN Communication Bus Performance
U0003
High Speed CAN Communication Bus (+) Open
U0003
High Speed CAN Communication Bus (+) Open
U0004
High Speed CAN Communication Bus (+) Low
U0004
High Speed CAN Communication Bus (+) Low
U0005
High Speed CAN Communication Bus (+) High
U0005
High Speed CAN Communication Bus (+) High