Fault codeP0382

SEVERE

Glow Plug/Heater Circuit B Malfunction

What this code means

Glow Plug/Heater Circuit B Malfunction.

P0382 is a generic code: it means the same thing on every make. P0382 belongs to family P03xx — Ignition and misfire. Its page explains how to read a code and groups all its codes by part.

Type of fault

The control unit has detected an electrical anomaly on this circuit without saying exactly which. Diagnosis starts with a visual check of the wiring and connector, then measuring the component — resistance, supply, ground — with a multimeter.

Glow plugs (diesel)

Glow plugs heat the combustion chambers of a diesel engine so that it starts in the cold, and on many engines they keep heating for a few minutes afterwards to reduce smoke and noise. A control unit or relay feeds them and checks their circuit.

What you notice

Hard starting in the cold, white smoke and rough running for the first minutes; nothing when the engine is warm.

How to check it

Measure the resistance of each glow plug with the wiring disconnected: a very high value means a plug is open. Check the relay or control unit and its connectors. Remove the plugs carefully, engine warm, as they tend to seize in the head.

What to do

Have it checked promptly. A misfire sends unburnt fuel into the exhaust and destroys the catalytic converter within a few dozen kilometres. If the light is flashing, stop driving.

Clearing a code switches the light off but repairs nothing: if the fault remains, the code comes back. Clearing a fault code yourself →

How to read this code

PPowertrain
0standardised code
3Ignition and misfire
82P0382