OBD-II · Engine and powertrain (P)
P0490
EGR control circuit high
What it means
The engine computer sees a high voltage fault in the EGR valve control circuit (the motor or solenoid drive).
Symptoms
- engine warning light
- EGR switched off, possibly reduced power
- sometimes rough running
Likely causes, most likely first
| No. | Cause |
|---|---|
| 01 | open circuit or control wire shorted to voltage |
| 02 | failed EGR motor/solenoid |
| 03 | corroded or unplugged connector |
What to check, step by step
- 01Inspect connector and wiring at the EGR valve.
- 02Measure the actuator resistance against specification.
- 03Check the circuit for a short to ground or to voltage.
- 04Replace the EGR valve if the actuator is faulty.