Powertrain, generic (extended)

P2C09 A Camshaft Profile Actuator Position Sensor B Circuit Bank 1

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modePossible

Position sensor B belongs to the second of the four intake actuators that slide the cam sleeves on GM's L3B; GM's tables call it intake Hall sensor 2. The sensors are thus one per actuator, not one per lift step: sensors A to C get J2012 codes, while GM puts the fourth (sensor D) under its own codes P30B0 to P30B3. P2C09 is the open-circuit test for sensor B. With the output energised the ECM expects a low impedance; 200 kilohms or more between signal and ground in 4 of 5 samples, supply above 11 V, set a Type A fault (19OBDG03D, 25OBDG03B). GM bulletins PIT5677 and 21-NA-149 list P2C09 for L3B trucks with chafed harnesses. Without feedback the ECM cannot confirm shifts, so lift switching is disabled. Low and High are P2C0B and P2C0C.

Likely causes

Loose, unplugged or corroded connector on actuator 2
Wire broken by harness chafing on the camshaft carrier (GM L3B bulletins)
Open circuit inside the actuator or its Hall element

Symptoms

  • Check engine light on in the first trip
  • Lift switching and cylinder deactivation locked out
  • Usually no noticeable change in driving apart from fuel use

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

a camshaft profile actuator pos sensor b b1wiring harnessecm

Related codes

P2C05P2C0AP2C0BP2C0CP2C0DP2C16

References: gsi.ext.gm.com, gsi.ext.gm.com, gm-techlink.com, static.nhtsa.gov.