What it means
The cylinder 2 glow plug circuit is not performing within the expected range. The cause may be the glow plug, its wiring or connections, or the control circuit.
At a glance
- Usually lights the check-engine light
- Affects emissions; the car can fail an emissions test
How it works
The glow plug in cylinder 2 heats the combustion chamber to support cold starting in a diesel engine. The control module sets P06BA when it detects that the cylinder 2 glow plug circuit's response or operation is outside its expected range.
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
- Record freeze-frame data and note ambient and engine temperature, since the fault may be most apparent during cold-start preheating.
- Inspect the cylinder 2 glow plug connector and wiring for corrosion, looseness, heat damage, or chafing.
- With the ignition off and following the vehicle's service procedure, compare cylinder 2 glow plug resistance with the manufacturer's specification and with the other plugs.
- Check the cylinder 2 circuit for continuity and unwanted shorts, and verify the glow plug control unit supplies the circuit as specified.
- If wiring and supply are sound, test or remove the cylinder 2 glow plug using the specified procedure and replace it if it fails.
Common fixes
- Reconnect or clean the cylinder 2 glow plug connector.
- Repair damaged wiring in the cylinder 2 glow plug branch.
- Replace the cylinder 2 glow plug if its test result is outside specification.
- Repair or replace the glow plug control unit if testing confirms it is not controlling the cylinder 2 circuit correctly.
Can I keep driving?
The vehicle may start and run poorly in cold weather, with white smoke during warm-up; avoid repeated long cranking, which can drain the battery and stress the starter. Arrange repair soon, especially if cold starting becomes unreliable.
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.