P0403moderate severityPowertrain
EGR Control Circuit
on 2004 Subaru Legacy 3.0L H6 · AWD
What this code 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
Repair notes
Replace EGR valve or repair wiring.
Other Powertrain codes on this vehicle
P0001
Fuel Volume Regulator Control Circuit/Open
P0002
Fuel Volume Regulator Control Circuit Range/Performance
P0003
Fuel Volume Regulator Control Circuit Low
P0004
Fuel Volume Regulator Control Circuit High
P0010
Intake Camshaft Position Actuator Circuit/Open Bank 1
P0011
Intake Camshaft Position Timing Over-Advanced Bank 1
P0012
Intake Camshaft Position Timing Over-Retarded Bank 1
P0013
Exhaust Camshaft Position Actuator Circuit/Open Bank 1
P0014
Exhaust Camshaft Position Timing Over-Advanced Bank 1
P0015
Exhaust Camshaft Position Timing Over-Retarded Bank 1