P0380 code meaning
Glow Plug/Heater Circuit A
Powertrain system Generic code P03xx codes Check engine light
What P0380 means
P0380 concerns glow plug circuit A – depending on the manufacturer the first group of plugs, glow relay 1 or feedback line A of the glow plug control module. Saab's 3.0 TiD (9-5, 2002) has two feedback lines from the control module; if line A at the engine module stays above 4.0 V for more than 3 s while glowing, the module is reporting a plug or circuit fault, checked once per drive cycle with the warning lamp on. In Saab's 1.9 TiD (EDC16) the glow plug control module drives two pairs of plugs, monitors them itself and reports faults over a diagnostic line that should switch inversely to the activation line. The 2010/11 Saab 9-5 2.0 TiD sets P0380 for implausible feedback or a missing supply of the module, there without check engine light. Newer GM and Ford diesels report single plugs under P0671 ff instead.
P0380 at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modeNot expected
- Repair difficultyMedium, DIY possible
- Typical labor0.5 to 4 hours
- Clears after repairWhen cleared with a scanner
Symptoms of P0380
- Hard starting when cold, long cranking
- White or blue smoke and rough running after a cold start
- Glow plug light or check engine light on or flashing
Common causes of P0380
- Most likelyGlow plug(s) in circuit A burnt out
- PossibleGlow plug control module or glow relay faulty
- PossibleWiring or connector fault (feedback line, plug connector, supply)
- Less likelyMissing battery or ignition supply of the control module (fuse)
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Glow plugGlow plug control moduleGlow plug relayGlow plug wiring
What each part of P0380 means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 0 | Generic code: it means the same on every make (SAE standard). |
| 3 | Area: ignition system or misfire. |
| 80 | The exact fault in that area. |
What to do next
- Note P0380 and any other codes stored with it: several codes together often point to one cause.
- Check for loose connectors and damaged wiring around the parts the code names.
- Check open recalls for your car: some faults are fixed for free by the dealer. Enter your VIN.
- Clear the code only after the repair. If it comes back, the fault is still there.
Buying a used car? Scan it for stored codes before you pay. A recently cleared memory can hide a problem.
Questions about P0380
What does P0380 mean?
P0380 means "Glow Plug/Heater Circuit A". P0380 concerns glow plug circuit A – depending on the manufacturer the first group of plugs, glow relay 1 or feedback line A of the glow plug control module. It is a generic code, so it means the same on every make.
Is it safe to drive with P0380?
Usually yes, for a short time, if the check engine light is steady and the car drives normally. If the light flashes or the car runs badly, stop and have it checked.
Will P0380 fail an emissions test?
Yes, it can. P0380 is emissions-related, so most inspection programs fail a car while it is stored or while the check engine light is on.
How hard is P0380 to fix?
Difficulty: medium. A typical repair takes 0.5 to 4 hours of work. A careful DIY repair is possible with basic tools and a scanner.
Will P0380 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.