P2B44A Camshaft Position Actuator Position Sensor B Range/Performance Bank 2
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- Needs a drive cycle to confirm a fix
- How the car detects it
- P2B44 is the one code of this group with a public manufacturer use. Mercedes-Benz bulletin LI05.20-P-080192 (January 2026) lists P2B4400 on M176/M177 V8 engines – AMG 63 models, S 580, G 550, GLS 580 – and reads it as an implausible sensor signal from CAMTRONIC solenoid 2 on the intake side of bank 2. The bulletin blames software and hardware: update the engine control unit, fit the newest actuator part numbers and inspect the harness near the windshield for heat damage. Related codes in the same bulletin show the system then going into limp-home mode (P164B). In short, the signal is electrically present but disagrees with the pin movement that was commanded. Bank 1 counterpart: P2B40.
- What you may notice
- Check engine light on
- CAMTRONIC limp-home mode, cylinder deactivation off
- Higher fuel consumption at part load
- Likely causes
- LikelyEngine control software needs the CAMTRONIC update (Mercedes)
- LikelyActuator of an older part number (Mercedes replaces it)
- PossibleHarness heat-damaged near the windshield
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Workshop only · Usually a job for a workshop.Typical cost: €150 – €1,000
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.