P0490
PowertrainEgr Systemmoderate severityEGR Control Circuit High
What P0490 Means
The PCM has detected a high voltage condition in the EGR control circuit. This may indicate an open circuit or wiring fault affecting EGR operation.
Symptoms
- Check engine light on
- Rough idle
- Increased emissions
Common Causes
- Open circuit in wiring
- Faulty EGR valve
- Corroded connector
- Faulty PCM
Diagnostic Steps
- Scan for stored codes
- Check EGR control circuit voltage
- Inspect wiring for opens
- Test EGR valve operation
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✓ Autel official store
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