What it means
B Camshaft Position Actuator Position Sensor C Circuit Low (Bank 1): the signal 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 position actuator position sensor C sends an electrical position signal to the engine control module. This code sets when that signal voltage is below its expected range, which can result 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 sensor C position reading when the low-signal fault occurs.
- With the ignition off, inspect the sensor C connector and Bank 1 harness for rubbed-through insulation, moisture, corrosion, or a wire touching ground.
- Check connector fit and terminals for corrosion or looseness that could lower the signal.
- Use the wiring diagram and manufacturer’s procedure to test the sensor C signal wire for a short to ground and check circuit continuity.
- If wiring and terminals pass, test the sensor supply, ground, and output to the manufacturer’s specification.
Common fixes
- Repair sensor C wiring shorted to ground or insulation damaged by chafing.
- Clean or repair corroded or loose connector terminals.
- Repair any open or damaged section of the Bank 1 sensor signal circuit.
- Replace sensor C only if circuit tests confirm the sensor is producing a low signal.
Can I keep driving?
Limit driving and avoid hard acceleration because the module may not receive reliable Bank 1 actuator position feedback, causing power loss or stalling. Stop if the engine runs very roughly or stalls.
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.