Powertrain, generic (extended)

P2B47 B Camshaft Position Actuator Position Sensor B Circuit Bank 1

Check engine lightOn

EmissionsRelevant

Drive cycleNot required

Limp modePossible

P2B47 moves the circuit fault to the exhaust side: it concerns position sensor B on the actuator of camshaft B, bank 1. NTN-SNR's supplier code list reads camshaft B as the outlet camshaft. Mercedes-Benz, in its CAMTRONIC bulletin for the M176/M177 V8, documents exhaust-side feedback faults only for sensor A of solenoid 1 (P34BD, P34BE); a second exhaust sensor and P2B47 itself are not documented publicly by any manufacturer. The comparable GM L3B judges an exhaust sliding-cam feedback circuit (P2C12) as open from 200 kΩ upward, 4 of 5 samples, MIL on the first trip. Look for an unplugged or corroded connector and broken wires first. The intake-side counterpart on bank 1 is P2B3F.

Likely causes

Connector unplugged or corroded, wire broken

Exhaust actuator sensor failed

Engine control module fault

Symptoms

Check engine light on
Exhaust cam lift change unavailable
Little change in driving behaviour

Repair estimate

DifficultyMediumWorkshop job

Parts and labour€80–650

Time0.5–3 h

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

b camshaft position actuator pos sensor b b1wiring harnessecm

References: law.cornell.edu, ntn-snr.com, static.nhtsa.gov, gsi.ext.gm.com.