What it means
B Camshaft Profile Actuator C Control Circuit Low (Bank 1): the control-circuit voltage is below the expected range. This relates to engine timing; a fault can cause rough running, a no-start, or timing errors.
At a glance
- Usually lights the check-engine light
- Affects emissions; the car can fail an emissions test
How it works
The Bank 1 B camshaft profile actuator C control circuit operates a mechanism that changes the cam profile. The engine control module monitors the circuit while commanding that change; this code sets when the monitored voltage falls below its expected range, such as from a short to ground or a poor connection.
Common causes
Most likely first.
- Short to ground
- Connector pins corroded - high contact resistance
- Harness chafing through insulation
Symptoms
- Check engine light on
- Power loss especially in mid-rpm range
- Possible rough idle or stalling
- Increased fuel consumption
How to diagnose it
- Record freeze-frame data and check live data for the Bank 1 actuator C command and related cam timing to see when the low-circuit fault occurs.
- With the ignition off, inspect the actuator C connector and Bank 1 wiring for corrosion, backed-out pins, or insulation rubbed through to ground.
- Check connector fit and terminal condition, since corrosion or loose contact can disrupt the control circuit.
- Use the wiring diagram and manufacturer’s procedure to test the actuator C control wire for a short to ground and check continuity between the module and actuator.
- If the wiring and terminals pass, test the actuator and module circuit according to the manufacturer’s specification before replacing either part.
Common fixes
- Repair chafed Bank 1 actuator C wiring that is shorted to ground.
- Clean or repair corroded or loose connector terminals.
- Repair an open or damaged section of the actuator C control wire.
- Replace the actuator or repair the module circuit only if testing identifies it as faulty.
Can I keep driving?
A short trip may be possible if the engine runs smoothly, but avoid hard acceleration because reduced mid-range power, stalling, or incorrect cam timing can worsen. Stop driving if it stalls or runs very roughly.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.