Powertrain, generic (extended)

P2C1A B Camshaft Profile Actuator Position Sensor C Circuit Bank 1

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modePossible

P2C1A would report an open circuit in a third position feedback on the bank 1 exhaust camshaft. No manufacturer documents this code publicly. GM's L3B, the one engine with publicly documented exhaust feedback codes, has just two exhaust Hall sensors (P2C12 to P2C19), in line with the two exhaust profile actuators that GM TechLink describes; its 2019 and 2025 tables contain no P2C1A. A system with a third exhaust actuator would test it as with the analogous code P2C16: an energised driver and a very high signal-to-ground impedance pointing to a broken wire. CARB requires such sensors and actuators of a valve lift system to be monitored for circuit faults. Expect a warning lamp and a locked exhaust lift profile.

Likely causes

Disconnected or corroded plug at the third exhaust actuator
Broken feedback wire in the engine harness
Internal open in the position sensor

Symptoms

  • Engine warning lamp on
  • Exhaust cam profile switching locked out

Repair estimate

DifficultyMediumWorkshop job
Parts and labour€50–900
Time0.5–4 h

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

Parts involved

b camshaft profile actuator pos sensor c b1wiring harnessecm

Related codes

P2C1BP2C1CP2C1DP2C16P2C0DP03F1

References: law.cornell.edu, gsi.ext.gm.com, gm-techlink.com.