What it means
The ECM cannot read a valid ion current signal from cylinder 10. Ion current sensing relies on the spark plug acting as an electrode after combustion.
At a glance
- Usually lights the check-engine light
- Affects emissions; the car can fail an emissions test
How it works
The ion-current system uses the cylinder 10 spark plug as an electrode after combustion so the ECM can read a signal related to combustion. This code sets when the ECM cannot obtain a valid cylinder 10 ion-current signal, commonly due to a failed ion-sense module or a wiring or connector fault.
Common causes
Most likely first.
- Ion sense module failed
- Wiring or connector fault
Symptoms
- Check-engine light
- Engine misfire or rough running
- Reduced power
How to diagnose it
- Save freeze-frame data and check live misfire or ion-current information to confirm the fault is associated with cylinder 10 and note the conditions when the signal is invalid.
- Inspect the cylinder 10 sense wiring and connector for disconnection, chafing, heat damage, corrosion, or loose terminals.
- Check the cylinder 10 spark plug and ignition connections for visible damage or contamination.
- Use the wiring diagram to test the cylinder 10 sense circuit for opens and shorts, following the manufacturer's specification.
- If the wiring and connections pass, test the ion-sense module and its cylinder 10 channel using the vehicle's specified procedure.
Common fixes
- Reconnect or clean and secure the cylinder 10 sense-circuit connector.
- Repair an open, shorted, or damaged cylinder 10 sense wire.
- Replace a cylinder 10 spark plug if inspection shows it is damaged or fouled.
- Replace the ion-sense module if circuit testing confirms it has failed.
Can I keep driving?
If the warning light is steady and the engine runs smoothly, a short gentle drive for diagnosis may be possible, but the fault can impair misfire monitoring and increase emissions. Stop if the engine misfires severely or loses power, and avoid heavy acceleration.
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.