P2C2ATurbocharger/Supercharger Bypass Valve B Position Sensor Circuit/Open
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- How the car detects it
- P2C2A covers an open or otherwise unreadable position feedback from compressor bypass valve B, the electrically positioned recirculation valve of the second charger. Without a valid feedback the engine module cannot confirm how far the valve has opened, which an Achates Power patent names as the reason such sensors are monitored. No manufacturer documents P2C2A publicly. GM's 2019 tables describe the A-side sensor of the supercharged LT5 as a ratiometric signal relative to the 5 V reference, but publish only its low and high codes P2BBC/P2BBD. GM defines charger A as bank 1 in parallel layouts and first in exhaust flow in series layouts, so B is the other one. Wiring and connectors near the hot charger are the usual suspects; boost is often limited.
- What you may notice
- Check engine light
- Boost limited, less power
- Likely causes
- LikelyUnplugged, loose or corroded connector at valve B
- PossibleBroken signal, reference or ground wire of the sensor
- PossibleInternal open in the position sensor of the actuator
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Medium · Usually a job for a workshop.Typical cost: €60 – €900
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.