P0405 Code: Exhaust Gas Recirculation (EGR) Position Sensor A Circuit Low
🟠 Moderate severity · drivable
Drivable, but the EGR valve position can't be read correctly, which can affect idle and emissions.
What P0405 means
The EGR valve position sensor (circuit A) is reporting voltage that's too low. The computer can't tell how far the EGR valve is open.
Symptoms
- Check engine light is on
- Rough idle
- Possible stalling
- Failed emissions test
Common causes
- most common: Faulty EGR valve position sensor
- common: Shorted or damaged wiring
- less common: Corroded connector
How to fix it
| Fix | DIY? | Typical cost |
|---|---|---|
| Replace the EGR valve (position sensor is usually built in) | Yes | $100–400 |
| Repair shorted sensor wiring | Mechanic | $50–150 |
Frequently asked questions
Can I drive with a P0405 code?
Yes, but the EGR valve position can't be read, which can affect idle and emissions.
What is the most common cause of P0405?
A faulty EGR valve position sensor, which is usually part of the EGR valve itself.
How much does it cost to fix a P0405?
Typically $100–$400 for a new EGR valve.
Related codes
P0404
P0404 Code: Exhaust Gas Recirculation (EGR) Circuit Range/Performance
P0406P0406 Code: Exhaust Gas Recirculation (EGR) Position Sensor A Circuit High
P0403P0403 Code: Exhaust Gas Recirculation (EGR) Circuit Malfunction
Updated 2026-08. This page is informational and not a substitute for professional diagnosis.