Parts
$30–120
P0403 — Exhaust Gas Recirculation Circuit
SAFEIs it safe to drive? A wiring or solenoid fault in the EGR circuit — emissions failure but not a safety concern; drivable until your next shop visit.
What P0403 means
The ECM commanded the EGR solenoid and didn't get the expected feedback voltage. 'Circuit' means the fault is electrical — the valve or solenoid may be fine, but the wiring, connector, or solenoid coil has an open or short.
Most likely causes (in order)
- EGR solenoid coil open or shorted (measure resistance at the connector)
- Connector corroded or broken pin
- Wiring harness chafed or cut
- Vacuum-operated EGR with failed control solenoid
- Fuse for EGR control circuit blown
Symptoms you might notice
- CEL only (often no driveability symptom)
- possible rough idle if EGR stuck open as result
What to check first
Measure EGR solenoid resistance at the connector — most solenoids read 20–70 ohms. An open (OL) or dead short (near 0) reading confirms the solenoid coil, not the wiring. If resistance is correct, check voltage supply to the connector.
Repair cost & difficulty
Labor
0.5–1.5 hr
Difficulty
DIY-friendly