What it means
Knock sensor D signal is in electrical range but plausibility check fails — typically a loose mounting, wrong torque, or sensor element drift.
At a glance
- Usually lights the check-engine light
- Affects emissions; the car can fail an emissions test
How it works
Knock sensor D detects combustion-related vibration and reports it to the engine control module so ignition timing can be adjusted. This code means the signal is present, but its pattern or level does not behave as the module expects; a loose or incorrectly mounted sensor can distort what it detects.
Common causes
Most likely first.
- Sensor loose
- 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
- Save freeze-frame data and compare sensor D's live reading with other available knock-sensor readings under the same operating conditions.
- Identify sensor D using the vehicle's service information and check that it is mounted firmly at the correct location.
- Inspect the sensor D connector and nearby harness for corrosion, pin damage, chafing, or tension that could affect the signal.
- Check for engine or timing-related faults that could create unusual vibration and make sensor D's reading implausible.
- Test sensor D and its wiring using the manufacturer's procedure; if they pass, investigate any related gateway or CAN communication faults.
Common fixes
- Correct sensor D's mounting if it is loose or incorrectly installed.
- Clean or repair a poor sensor D connector contact.
- Repair chafed or damaged wiring in sensor D's circuit.
- Replace knock sensor D if its signal fails the manufacturer's tests.
- Repair a confirmed gateway or CAN network fault.
Can I keep driving?
Keep driving only gently and for as little as practical until checked; avoid high engine loads because the module may not reliably detect knock through sensor D. Stop if you hear persistent knocking or the engine loses substantial power.
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.