Powertrain, generic · Ignition system or misfire

P03EC A Camshaft Profile Actuator C Control Circuit/Open Bank 1

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modePossible

With a sliding camshaft, the intake camshaft (camshaft A) carries movable cam pieces with several lift profiles; solenoid actuators shoot a pin into a groove in the piece and shift it axially. Actuator C is the third of these actuators – not a profile position. The only known user is GM's 2.7-litre turbo four (L3B, three-step sliding cam, from model year 2019). P03EC means the actuator's control circuit is open: GM checks the circuit with the driver on and sets the code at an impedance of 200 kΩ or more (4 of 5 samples, above 11 V, MIL on the first trip). The actuator can then not shift its cam piece, and lift switching and cylinder deactivation are blocked.

Likely causes

Actuator connector loose, corroded or pin pushed back (often after valve cover work)
Actuator solenoid open
Wire broken in the engine harness
Driver in the engine module

Symptoms

  • Check engine light on
  • Lift switching and cylinder deactivation blocked, higher consumption
  • Possibly rough running if a cam piece stays in the wrong position

Repair estimate

DifficultyMediumWorkshop job
Parts and labour€100–600
Time0.5–2.5 h

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

Parts involved

camshaft profile actuator c intakesliding camshaftactuator wiringengine control module

Related codes

P03EDP03EEP03F1P001AP037C

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