Powertrain, generic (extended)

P2C16 B Camshaft Profile Actuator Position Sensor B Circuit Bank 1

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modePossible

P2C16 is the open-circuit fault of position sensor B on the bank 1 exhaust camshaft. On GM's L3B this is exhaust Hall sensor 2, the second and last exhaust feedback: GM's tables list four exhaust pin drivers (control codes P002A, P2B39, P03F1, P3099) but only two exhaust Hall elements, which matches the two exhaust profile actuators described by GM TechLink. The ECM energises the driver and treats 200 kilohms or more from signal to ground in four out of five samples above 11 V as an open circuit, Type A, MIL immediately (19OBDG03D, 25OBDG03B). P2C16 is part of the main DTC list of PIT5677 and 21-NA-149. Possible causes are a pulled connector, a broken wire or an open Hall element; until fixed, exhaust lift switching is disabled.

Likely causes

Plug on exhaust actuator 2 pulled off or not locked after engine work
Wire broken where the harness rubs at the camshaft carrier (GM L3B bulletins)
Open circuit in the Hall element of actuator 2

Symptoms

  • Check engine light in the first trip
  • Exhaust lift switching and economy modes blocked

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 b b1wiring harnessecm

Related codes

P2C12P2C17P2C18P2C19P2C09P2B39

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