Powertrain, generic (extended)

P2B48 B Camshaft Position Actuator Position Sensor B Range/Performance Bank 1

Check engine lightOn

EmissionsRelevant

Drive cycleRequired

Limp modePossible

P2B48 is the plausibility code for sensor B at the bank 1 exhaust actuator (camshaft B): the circuit works, yet the reported position contradicts the command. Mercedes handles this fault type on its CAMTRONIC V8s for the exhaust sensor of solenoid 1 as P34BD and fixes it through software and newer actuators; P2B48 itself is not found in any public manufacturer source. GM's L3B gives an idea of the logic under P2C13: the exhaust Hall feedback must pass through three states per shift, and a signal without a shift command also counts as an error. Carbon or sludge on the actuator pin, worn parts or a damaged shift groove can cause the mismatch. Bank 2 counterpart: P2B4C.

Likely causes

Actuator pin sticking from deposits or wear

Outdated engine control software

Shift groove or cam sleeve damaged

Symptoms

Check engine light on
Exhaust lift switching held in one position
Possibly rough running during shift attempts

Repair estimate

DifficultyHardWorkshop job

Parts and labour€100–900

Time1–4 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.