P2B39B Camshaft Profile Actuator B Control Circuit/Open Bank 1
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- How the car detects it
- Camshaft B is the exhaust camshaft, and actuator B is the second shifting solenoid on it. On GM's 2.7-litre L3B the exhaust side has only two such actuators, so this is the last of them; GM's tables call it exhaust camshaft profile actuator 2. P2B39 flags an open control circuit: with the output commanded on, the ECM reads an impedance of at least 200 kΩ to ground. It needs 4 failures in 5 samples, a supply above 11 V and key in crank or run, and it turns the MIL on in the first trip. A loose connector on the camshaft carrier, a broken wire or an open coil are the usual causes. The exhaust sleeve then stays put, so the engine cannot change profile on that side. The intake counterpart is P2B33.
- What you may notice
- MIL on in the first drive
- Exhaust lift profile no longer switches, cylinder deactivation unavailable
- Likely causes
- LikelyExhaust actuator connector loose or corroded on the camshaft carrier
- PossibleBroken wire in the engine harness
- PossibleOpen solenoid coil in exhaust actuator B
- 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: €80 – €600
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.