P03F5: B Camshaft Profile Actuator C Control Stuck On Bank 1

With a sliding camshaft, the exhaust camshaft (camshaft B) 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). P03F5 means the actuator stays on: its pin remains extended although it was commanded off. No manufacturer document available to us uses this code – GM monitors its exhaust actuators only for circuit faults and uncommanded extension; the description follows the intake counterpart P03F0, where GM sets the code if the pin does not retract by the end of the engine cycle.

Medium severity. Can I keep driving?Drive little and gently. If you hear timing chain noise or the oil light comes on, shut off the engine.

Bank 1 is the side of the engine with cylinder 1. Inline engines only have this bank.

Symptoms

Check engine light on
Ticking or rattling at the camshaft carrier
Misfire, rough idle or less power in the wrong lift profile
Lift switching and cylinder deactivation out of service

Most likely causes

Pin sticking in the actuator (sludge, wear)
Return ramp of the shift groove damaged or cam piece sticking
Solenoid stays energized (control wire shorted to ground)
Hall feedback faulty

What to check, in order

Start with the simplest. You can tick off each step.

Check the oil level and condition before anything else
Use the scanner to command the movement and compare the actual position with the requested one.
Check the solenoid valve's connector
Compare commanded and actual angles in live data
Test the solenoid valve and its filter, if it has one
Check the engine timing if there is chain noise

Good to know

Repair difficulty: hard
It can trigger limp mode.
It affects emissions.

What each character of P03F5 means

P: Powertrain: engine and transmission
0: Generic code: same on every make
3: Ignition and misfires
F5: Specific fault in that system

Frequently asked questions

Can I keep driving with code P03F5?

Drive little and gently. If you hear timing chain noise or the oil light comes on, shut off the engine.

What causes code P03F5?

The most common causes are: pin sticking in the actuator (sludge, wear); return ramp of the shift groove damaged or cam piece sticking; solenoid stays energized (control wire shorted to ground).

Related codes

Sources

Values and procedures vary by manufacturer. If it affects brakes, steering, fuel or high voltage, see a professional. Updated: 2026-11-04. How we build these pages.