What it means
The glow plug control module 1 has a performance fault. This can affect diesel preheating, but the specific impact depends on the vehicle.
At a glance
- Usually lights the check-engine light
- Affects emissions; the car can fail an emissions test
How it works
Glow Plug Control Module 1 controls diesel engine preheating, including operation of the glow plugs before and during cold starts. P06E5 sets when the engine controller detects that Module 1 is not performing as expected, which can result from the module, its wiring, or its power and ground supply.
Common causes
Most likely first.
- Glow plug control module fault
- Wiring or connector fault
- Module power or ground 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 scan for individual glow plug circuit codes that could reveal whether the performance fault is limited to a plug or circuit.
- Check the battery and inspect Glow Plug Control Module 1 power and ground connections for poor contact or damage.
- Inspect the module connector and harness for corrosion, loose pins, or chafing.
- Use a scan tool to compare commanded preheating with module response, if the vehicle provides those data.
- If supplies and wiring pass, test Glow Plug Control Module 1 and its outputs according to the manufacturer's procedure.
Common fixes
- Restore battery condition or repair poor power and ground connections to Module 1.
- Repair damaged or corroded wiring and connector terminals at the module.
- Repair any glow plug circuit fault identified by related codes and testing.
- Replace Glow Plug Control Module 1 if it fails the manufacturer's performance checks.
Can I keep driving?
Cold starting may be difficult or fail in low temperatures, and white smoke can occur during warm-up. If the engine starts and runs normally, limit use in cold weather until the preheating system is checked.
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.