Powertrain
generic / SAE
P0039
Turbocharger/Supercharger Bypass Valve A Control Circuit Range/Performance
The wastegate or bypass valve A on the turbo/supercharger does not respond mechanically as expected to its control signal. Boost pressure deviates from target.
SystemPowertrain
Typegeneric / SAE
GroupP0
Range / number– / 39
Possible causes
- Wastegate sticking from carbon high
- Vacuum/boost line leaking medium
- Wastegate actuator worn medium
Symptoms
- Charge status indicator shows fault
- Charging may not start or interrupts
- Slower-than-expected charge rate
Inspection / repair
- Difficulty: medium
- DIY: shop recommended
- Estimated cost: 150–1500 €
- Estimated time: 1–6 h
- Component: wastegate actuator
- Component: bypass valve
- Component: boost pressure sensor
- MIL / check engine light
- emissions-relevant
- drive cycle required
- limp mode possible
Sources
References
sae:J2012