OBD-II FAULT CODE
U2021
Invalid /fault data received (Non SCP)
Meaning, symptoms, likely causes, diagnostic checks and repair guidance for U2021.
- Multiple warning lights or modules not communicating
- Low battery voltage
- Blown module fuse
- Poor ground
- Open/short on communication bus
- Module offline
- Check battery condition, module fuses, grounds and network connectors before replacing modules
- Run a full system scan to identify modules not responding
- Inspect CAN/SCP wiring, connectors and grounds
- Repair power/ground or network wiring fault first
- Only consider module replacement after wiring and power supply checks pass
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Disclaimer: Information is provided for general guidance only and may not apply to all vehicles. Always consult a qualified technician.