What it means
Knock sensor C signal jumps or drops out intermittently — usually a corroded connector or chafed wire near the cylinder head.
At a glance
- Usually lights the check-engine light
- Affects emissions; the car can fail an emissions test
How it works
Knock sensor C detects combustion-related vibration on engines equipped with multiple knock sensors so the control module can adjust ignition timing. P032E sets when the sensor C signal intermittently jumps or drops out, often because of a loose or corroded connector or chafed wiring.
Common causes
Most likely first.
- Intermittent connector
- Gateway module routing CAN messages incorrectly
- CAN terminating resistor (120 Ω) drifted out of spec
Symptoms
- Check-engine light
- Reduced engine power or acceleration
- Engine knocking may be more noticeable
How to diagnose it
- Review freeze-frame data and live readings for sensor C to identify when the signal becomes intermittent and check for related codes.
- Locate sensor C using vehicle service information and inspect its connector and nearby harness for corrosion, looseness, or chafing.
- With the engine off, carefully move the accessible sensor C harness while monitoring the circuit for an intermittent change, keeping clear of hot or moving parts.
- Check for intermittent opens or poor connections in the sensor C wiring between the sensor and control module using the manufacturer's procedure.
- If the connections and harness are sound, test knock sensor C for intermittent failure.
Common fixes
- Secure or repair a loose or corroded sensor C connector.
- Repair chafed or intermittently open wiring in the sensor C circuit.
- Replace knock sensor C if it intermittently fails testing.
Can I keep driving?
Drive gently and avoid heavy loads because power may be reduced and knock detection for sensor C's monitored area may be unreliable during signal dropouts. Stop if you hear sustained engine pinging.
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.