What it means
The control circuit of camshaft profile actuator B on the exhaust side of bank 1 reports a control stuck on condition. Cam profile B (high-lift or VTEC-style) cannot be commanded reliably.
At a glance
- Usually lights the check-engine light
- Affects emissions; the car can fail an emissions test
- The engine or gearbox may go into limp mode
How it works
Camshaft profile actuator B on the exhaust side of bank 1 changes the exhaust valves to a different lift profile. The module monitors its control and response; this code sets when the actuator stays on or in the high-lift state rather than releasing when commanded.
Common causes
Most likely first.
- Actuator stuck in high-lift position
- Release pressure path blocked
- Carbon or debris buildup preventing free movement
Symptoms
- Check engine light on
- Power loss especially in mid-rpm range
- Possible rough idle or stalling
- Increased fuel consumption
How to diagnose it
- Review freeze-frame data and the commanded versus reported profile state for bank 1 exhaust actuator B to identify when it failed to release.
- Inspect the bank 1 exhaust actuator B connector and wiring for damage, oil contamination, corrosion, or a poor fit.
- Check engine oil level and condition because a blocked hydraulic release path can hold the exhaust profile engaged.
- If the scan tool supports active tests, command bank 1 exhaust actuator B on and off and observe whether its reported state follows.
- Test the actuator circuit and inspect the exhaust-side actuator and release path for sticking or carbon and debris, using the manufacturer's procedure.
Common fixes
- Correct low or unsuitable engine oil if present.
- Repair the bank 1 exhaust actuator B connector or damaged wiring.
- Clean an obstructed release path or remove buildup that prevents the exhaust profile mechanism from releasing.
- Repair or replace bank 1 exhaust actuator B if testing confirms it sticks on.
Can I keep driving?
A steady warning light with otherwise normal running may allow a short, gentle trip, but avoid hard acceleration because power loss or stalling is possible. Stop driving if the engine stalls or runs very roughly; continued use can increase fuel consumption and drivability problems.
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.