P0403 Exhaust Gas Recirculation Circuit Malfunction
What does P0403 mean?
P0403 — Exhaust Gas Recirculation Circuit Malfunction. This is an OBD-II diagnostic trouble code a scanner retrieves when your vehicle's computer detects exhaust gas recirculation circuit malfunction. The level of risk depends on how the vehicle is currently running and how long you've been driving with the light on.
Common causes of P0403
- Faulty EGR valve solenoid or motor
- Open or shorted EGR control circuit
- Poor connector contact
- Blown fuse for the EGR circuit
- PCM fault
How to fix P0403
- Check the EGR fuse and supply voltage
- Inspect EGR wiring and connector for damage or corrosion
- Actuate the EGR valve with an OBD-II scanner and confirm it responds
- Test the solenoid or motor resistance
- Replace the EGR valve or repair wiring per test results