P0382: Glow plug circuit B malfunction
The ECU has found an electrical fault in glow plug circuit B of the diesel engine. It is usually a failed glow plug, wiring or the control relay.
| Code | P0382 |
|---|---|
| System | Engine and transmission |
| Group | P03xx, Ignition and misfires |
| Type | Generic: it means the same on every make |
| Can you keep driving? | Yes, no rush |
What P0382 means
Diesel engines use glow plugs to help them start from cold. The ECU monitors their circuit and has seen something wrong in group or circuit B. Exactly what circuit B covers is decided by each manufacturer.
Most common causes
- Loose or corroded connector on a glow plug
- One or more burnt out glow plugs
- Damaged wiring or a poor earth in the circuit
- Faulty glow plug relay or control module
- Blown fuse in the glow plug circuit
Symptoms
- Hard starting when cold
- White or bluish smoke on start up
- Rough running for the first few seconds
- Engine or glow plug warning light on
Can you drive with P0382?
Yes, no rush Once warm the car drives normally. In cold weather it may struggle to start, so it is worth fixing before winter.
How to check it
Ask the garage to measure the resistance of each glow plug with a multimeter: one that reads open circuit has failed. If your reader shows glow plug data, check that the heating time changes with engine temperature.
How to read and clear P0382 with Final OBD
Plug an OBD2 scanner in under the steering wheel, switch the ignition on and open Final OBD. Under Faults you’ll see P0382 with this same explanation and whether it’s confirmed, pending or permanent.
With Free you read this code with its short description for nothing, and clear it if the engine stores it over standard OBD. With Pro you get the full explanation, how the car was running when it was logged (revs, temperature, load) and clearing in every control unit.
Clearing the code only turns the light off: if the cause is still there, it comes back. Clear it once it’s fixed, and not right before the ITV. It’s all in how to read and clear fault codes and in the ITV and OBD.
Similar codes
- P0365 Camshaft position sensor B circuit fault (bank 1)
- P0366 Camshaft position sensor B signal out of range (bank 1)
- P0380 Glow plug circuit A fault
- P0381 Glow plug indicator light circuit fault
- P0300 Random or multiple cylinder misfire
- P0301 Misfire detected in cylinder 1
- P0302 Misfire detected in cylinder 2
- P0303 Misfire detected in cylinder 3
P0382 is a generic code, so it means the same on any make, for example on Alfa Romeo, Cupra, Dacia, Jeep, Nissan, Škoda. See what Final OBD does on your car in makes and models.
What does code P0382 mean?
Diesel engines use glow plugs to help them start from cold. The ECU monitors their circuit and has seen something wrong in group or circuit B. Exactly what circuit B covers is decided by each manufacturer.
Can you drive with P0382?
Once warm the car drives normally. In cold weather it may struggle to start, so it is worth fixing before winter.
How do you clear P0382?
With an OBD2 scanner and an app like Final OBD, which clears it for free if it’s stored by the engine control unit. But clearing it only turns the light off: if the cause isn’t fixed, P0382 comes back.
Read it on your car
Final OBD reads the faults of every control unit for free, including each make’s own codes, and with Pro explains each one in plain English. Free clears engine faults at no cost.
Coming soon
Mid to late October 2026
If you want to try it in your car before anyone else, send us your email and we will add you as a tester.
info@finalobd.com