OBD-II FAULT CODE
P0403
Exhaust Gas Recirculation Circuit Malfunction
Meaning, symptoms, likely causes, diagnostic checks and repair guidance for P0403.
- Check Engine light
- Poor drivability or reduced fuel economy depending on fault
- Faulty related sensor/actuator
- Wiring or connector issue
- Poor ground/power supply
- Control module fault is possible but less common
- Scan all modules and record freeze-frame data before clearing codes
- Check battery voltage and related fuses
- Repair wiring/connector/fuse issues first
- Replace the related sensor/actuator only after testing confirms failure
- Use OEM service manual for brand-specific procedures
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Disclaimer: Information is provided for general guidance only and may not apply to all vehicles. Always consult a qualified technician.