U0006high severityNetwork
High Speed CAN Communication Bus (-) Open
on 2020 BMW 2 Series 3.0L I6 Turbo · AWD
What this code means
The CAN Low wire is open, disrupting high-speed CAN communication. CAN L carries the recessive low signal.
Symptoms
- Multiple modules lose communication
- Warning lights on
- Systems go offline intermittently
Common causes
- Broken CAN L wire
- Corroded CAN L terminal
- Connector damage
- Wiring harness break
Diagnostic steps
- Measure voltage on CAN L (should be ~2.5V idle, ~1.5V dominant)
- Check continuity of CAN L wire
- Inspect splice points and connectors
- Use scope to verify CAN L waveform
Repair notes
Locate and repair the open in the CAN L wire.
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Other Network codes on this vehicle
CC-ID-181
System Check Failed
CC-ID-181
System Check Failed
CC-ID-207
Central Electronics Failure, Stop Vehicle
CC-ID-207
Central Electronics Failure, Stop 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