P2B4DB Camshaft Position Actuator Position Sensor B Circuit Low Bank 2
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- How the car detects it
- A too-low signal from position sensor B at the bank 2 exhaust camshaft actuator sets P2B4D. In practice this is a signal wire touching ground, a shorted sensor, or a sensor that gets no supply. The closest documented case is P34C2 on Mercedes M176/M177 V8s, where solenoid 1 on the bank 2 exhaust side reports a sensor short to ground; P2B4D is not described by any manufacturer in public. That bulletin also points at heat-damaged wiring near the windshield, so inspect the harness on the bank 2 side behind the engine. Repairs range from a wire splice to a new actuator with integrated sensor. CARB requires low-signal faults of such sensors to be recognised. Exhaust high fault on bank 2: P2B4E.
- What you may notice
- Check engine light on
- Exhaust lift change on bank 2 out of action
- Possibly limp-home message of the lift system
- Likely causes
- LikelySignal wire touching ground (heat or chafe damage)
- PossibleSensor in the actuator shorted
- RareNo supply to the sensor
- 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 – €650
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.