P0382: Glow Plug/Heater Circuit B
A generic powertrain (engine and transmission) trouble code, same meaning on every brand.
Yes once running - starting is the concern.
Symptoms
- Hard cold starts
- White smoke at startup
- Check engine light in cold weather
Likely causes, most common first
- Glow plugs on circuit B failed
- Second relay or controller stage faulty
- Busbar or wiring fault
- Fuse blown
Read P0382 yourself before paying for diagnosis
A basic Bluetooth OBD-II scanner ($20-40) plugs into the port under the dashboard and shows this code with live sensor data on your phone - useful both for confirming the fix and for talking to a shop from an informed position.
What is going on and how it gets diagnosed
P0382 covers the B side of the glow system on engines that split their plugs into two banks or stages - common on V8 diesels and on designs that stage glow current to soften the electrical load.
When only one circuit faults, the comparison is built in: the controller drives both, so a controller failure usually takes both circuits while a wiring or plug failure takes one. Measuring each plug's resistance to ground - typically well under 2 ohms healthy, open when burned out - maps the whole system in fifteen minutes and turns the repair from guesswork into a shopping list.
Repair options and cost
Typical US independent-shop ranges, parts and labor. Dealers run higher; regional labor rates vary.
Frequently asked questions
Can I drive with P0382?
Yes once running - starting is the concern.
How much does it cost to fix P0382?
Typical US repair costs range from $20 for the simplest fix (fuse or relay) to $700 in the worst case. The right number depends on which cause your car has - see the causes list.
Related codes
The codes closest to P0382. They often appear together, and telling them apart is usually what narrows the diagnosis.
Definition per SAE J2012 standard nomenclature. Symptoms, causes and costs are editorial guidance - always confirm with a diagnosis of your specific vehicle.