P0033
Turbocharger Bypass Valve Control Circuit
The ECU detects an electrical fault in the turbocharger bypass (wastegate) valve control circuit. Voltage or current measured on the solenoid output deviates from expected values during commanded actuation.
- Check engine light: Yes
- Emissions related: Yes
- Repair difficulty: medium
Symptoms
- Charge status indicator shows fault
- Charging may not start or interrupts
- Slower-than-expected charge rate
Common causes
Ordered by how often each turns out to be the cause.
- Bypass solenoid failedCommon
- Open or shorted wiring to solenoidPossible
- Connector corrosion or poor contactLess likely
Parts involved
- Turbocharger Bypass Valve
- Wastegate Solenoid
- Wiring Harness
- ECM
P0033 is a generic OBD-II code defined by SAE J2012. Exact wording and diagnostic procedure vary by manufacturer and model. Code definitions are drawn from the public-domain OBDex dataset; the workshop notes are our own.