P0048
Turbocharger/Supercharger Boost Control A Circuit High
Boost control circuit A voltage above expected range — short to power or open ground in solenoid wiring.
- 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.
- Wiring shorted to batteryCommon
- Connector pins corroded - high contact resistanceLess likely
- Supply wire pinched against B+ sourceLess likely
Parts involved
- Boost Control Solenoid
- Actuator Wiring
P0048 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.