P2599
Turbocharger Boost Control Position Sensor A Performance - Stuck High
Position sensor A reports a value stuck near the high end of its travel — actuator stuck open (wastegate held wide open, VGT vanes seized at maximum opening) or sensor pegged high. Boost suffers — typically underboost on VGT, overboost-protection-off on wastegate.
- Check engine light: Yes
- Emissions related: Yes
- Repair difficulty: hard
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.
- Actuator mechanically stuck near high endCommon
Parts involved
- Turbo Actuator Position Sensor A
- Turbo Actuator
P2599 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.