Actuator or solenoid mechanically stuck, for example from sludge, varnish or wear; Low, dirty or wrong-grade engine oil, or poor oil pressure at the actuator; Blocked oil passage or oil control screen feeding the actuator; Wiring or connector fault, such as a short to supply or a corroded pin; Faulty cam position sensor or feedback signal causing a false reading; Worn cam profile switching parts, such as followers or lifters, or incorrect valve timing; Engine control unit fault or outdated software where the manufacturer has a known issue.

P005B

B Camshaft Profile Actuator A Control Stuck On Bank 1.

Generic
Powertrain
Generic code
Medium severity

How this code is built

P: SystemPowertrain
0: Defined bySAE, the same on every car
0: AreaFuel and air metering, auxiliary emission controls
5B: FaultThe specific fault in that area

What it means

P005B means the engine control unit has found the B camshaft profile actuator on Bank 1 stuck in the 'on' (activated) position when it was commanded off. The actuator switches the valve lift or cam profile. The ECU saw cam position, valve timing or actuator feedback that did not match the commanded state. Which camshaft is 'B' (intake or exhaust) and how the actuator works depends on the engine.

Symptoms

Engine warning light on
Reduced power or flat response at higher revs
Rough idle or uneven running
Poor fuel economy
Engine may enter limp mode with restricted revs
Ticking or irregular valvetrain noise on some engines

Possible causes

Actuator or solenoid mechanically stuck, for example from sludge, varnish or wearlikely
Low, dirty or wrong-grade engine oil, or poor oil pressure at the actuatorlikely
Blocked oil passage or oil control screen feeding the actuatorpossible
Wiring or connector fault, such as a short to supply or a corroded pinpossible
Faulty cam position sensor or feedback signal causing a false readingpossible
Worn cam profile switching parts, such as followers or lifters, or incorrect valve timingrare
Engine control unit fault or outdated software where the manufacturer has a known issuerare

How to diagnose

Read all stored and pending codes and the freeze frame data. Note engine speed, load, oil temperature and whether other cam timing or misfire codes are present.
Check the engine oil level, condition and grade against the manufacturer specification, and check the service history.
Visually inspect the actuator wiring and connector on Bank 1 for chafing, oil contamination, corrosion and poor pin tension.
Using a scan tool with live data, compare commanded and actual cam position or profile state, and look for the actuator staying on.
Test the actuator circuit for power, earth and signal, and measure the actuator coil resistance against the specification for that engine.
Check the cam position sensor signal and its wiring, and check the oil pressure with a gauge if the oil supply is suspect.
Remove the actuator and inspect it for sludge, a sticking pin or damage, and check the oil feed passage is clear.
Look up manufacturer technical bulletins and software updates for your model and engine.

How to fix

Change the engine oil and filter to the correct grade and specification, and correct the oil level.
Clean or replace a sticking actuator or solenoid, and clear any blocked oil feed passages or screens.
Repair or replace damaged wiring, terminals or connectors.
Replace a faulty cam position sensor if testing shows it is giving a wrong signal.
Repair worn cam profile switching components or correct the valve timing if inspection finds a fault.
Apply a manufacturer software update if a known calibration fault applies to this engine.

Can I keep driving?

Medium severity

The car can usually be driven carefully for a short time to get it checked, but performance and economy may suffer and the fault can worsen. Avoid hard driving and high revs, and stop if the oil pressure warning light comes on or you hear unusual engine noises.

Guide written by AI from the code's definition. Confirm with a diagnosis before replacing parts.