Powertrain, shared range

P34B1 A Camshaft Position Actuator Position Sensor A Range/Performance Bank 2

Check engine lightOn
EmissionsRelevant
Drive cycleRequired
Limp modePossible

P34B1 means the intake-side position sensor A of bank 2 delivers an electrically sound but implausible value. No public manufacturer document uses this code. The nearest published example is the bank 1 code P34AD on the 2022 Mitsubishi Outlander, where the electric phaser module checks the motor position against the intake camshaft sensor and flags a mismatch. Mercedes uses the same fault type on the exhaust side for its CAMTRONIC lift actuators (P34BD, P34C1); bulletin LI05.20-P-080192 answers it with an engine software update and actuators of a newer part number. On bank 2 an actuator that binds or has worn, a lost learned position or a camshaft signal problem (compare P0021) are likely. The bank 2 phaser is then locked at its base angle.

Likely causes

Actuator on bank 2 sticking or worn
Learned actuator position lost or software outdated
Bank 2 intake camshaft signal disturbed

Symptoms

  • Check engine light on
  • Bank 2 intake timing fixed, reduced power
  • Possibly further timing codes such as P0021

Repair estimate

DifficultyHardWorkshop job
Parts and labour€100–1,100
Time1–4.5 h

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

Parts involved

cam actuator a pos sensor b2

Related codes

P34B0P34B2P34B3P34ADP0021P2B44

References: law.cornell.edu, ntn-snr.com, mitsubishitechinfo.com, static.nhtsa.gov.