P0403
PowertrainEmission Controlsmoderate severityEGR Control Circuit
What P0403 Means
Malfunction in the EGR valve control circuit (electrical EGR valves).
Symptoms
- Check Engine Light
- EGR not functioning
- Increased emissions
Common Causes
- Faulty EGR valve
- Wiring damage
- PCM driver failure
- Corroded connector
Diagnostic Steps
- Test EGR valve solenoid resistance
- Check wiring
- Command EGR with scan tool
- Test PCM output
Where to start: Replace EGR valve or repair wiring.
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✓ Autel official store
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