What it means
The control module has detected an incorrect condition in the cylinder 5 glow plug circuit. The code does not by itself establish that the wrong plug type was fitted.
At a glance
- Usually lights the check-engine light
- Affects emissions; the car can fail an emissions test
How it works
The cylinder 5 glow plug heats the combustion chamber to help a diesel engine start and run cleanly when cold. The control module monitors the cylinder 5 glow plug circuit and sets this code when its electrical response is incorrect; the code alone does not show that an incorrect plug type was fitted.
Common causes
Most likely first.
- Faulty glow plug
- Damaged or corroded wiring or connector
- Glow plug control circuit fault
Symptoms
- Glow plug warning light on (often orange coil symbol)
- Hard cold start or no start in cold weather
- White smoke from exhaust during warm-up
How to diagnose it
- Check freeze-frame and live glow plug data to see when the cylinder 5 fault occurred and whether its response differs from other cylinders.
- Inspect the cylinder 5 connector and harness for corrosion, loose contacts, melted insulation, or rubbing damage.
- Test the cylinder 5 glow plug using the manufacturer's procedure and compare the result with the manufacturer's specification.
- Confirm the fitted cylinder 5 plug is specified for the vehicle, then check its wiring and connections for continuity using the wiring diagram.
- If the plug and wiring are sound, test the controller's cylinder 5 output and control circuit.
Common fixes
- Clean and firmly reconnect the cylinder 5 glow plug connector.
- Repair damaged or corroded cylinder 5 circuit wiring.
- Replace a failed or incorrect cylinder 5 glow plug with the specified type.
- Repair the glow plug control circuit or controller if testing identifies a fault.
Can I keep driving?
If the engine starts and runs smoothly, driving may be possible, but cold starts can become difficult and warm-up smoke may increase. Avoid repeated cranking if it will not start, since it can drain the battery; repair the fault before cold-weather use.
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.