P2B33A 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
- P2B33 concerns the second profile actuator on the intake camshaft (camshaft A) of bank 1. Such actuators are solenoids that extend a pin into a groove on a sliding cam sleeve and so move lobes of a different lift under the valves. GM uses the code on the 2.7-litre turbo four L3B (Silverado and Sierra 1500 from 2019), whose sliding cam system has four intake and two exhaust actuators; GM calls this one actuator 2. The ECM energises the output and flags an open circuit when it sees 200 kΩ or more between signal and ground in 4 of 5 samples, with supply above 11 V; MIL on the first trip (Type A). With the sleeve unable to move, lift switching and cylinder deactivation stay locked out. Low and High are P2B34 and P2B35.
- What you may notice
- MIL on after the first drive with the fault
- No change of intake lift profile, less pull or higher fuel use depending on the stuck profile
- Cylinder deactivation no longer engages
- Likely causes
- LikelyConnector at the actuator on the camshaft carrier loose, corroded or not latched after valve cover work
- PossibleSolenoid winding of actuator B open
- PossibleControl wire broken in the engine harness
- RareOutput stage in the engine control module faulty
- 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.