Code
U0001
Network
High-speed CAN communication bus
The high-speed CAN bus has a fault preventing communication.
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Most likely causes
- Shorted or broken CAN wires
- Failed module
- Bad connector
Symptoms you may notice
- Multiple warning lights
- Modules unreachable
Checks to run
- Measure CAN resistance (about 60 Ω)
- Inspect wiring and connectors
- Isolate modules one by one
Tools you may need
Multimeter
OBD-II scanner
Always diagnose before replacing. Codes share symptoms; confirm the cause with measurements before buying parts.