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DTC/P0380

P0380 : Glow Plug / Heater Circuit "A" Malfunction

Quick Answer
Faible GraviteConduite possible (a court terme)Electrique

P0380 is a diesel-only code meaning the engine control unit detected a fault in glow plug heater circuit "A" (the main glow plug circuit or its control relay). Glow plugs preheat the combustion chambers so a cold diesel can ignite. The ECU monitors the circuit for open or shorted wiring and a failed glow plug relay or module. Repairs typically run 60-400 EUR depending on whether a relay, wiring, or full plug set is needed.

Cout de reparation estimeDe 2 € a 480 €+, varie selon le vehicule

Que signifie P0380 ?

P0380 is a diesel-only code meaning the engine control unit detected a fault in glow plug heater circuit "A" (the main glow plug circuit or its control relay). Glow plugs preheat the combustion chambers so a cold diesel can ignite. The ECU monitors the circuit for open or shorted wiring and a failed glow plug relay or module. Repairs typically run 60-400 EUR depending on whether a relay, wiring, or full plug set is needed.

P0380 est un code defaut lie a electrique, classe en gravite low. Lorsque le calculateur de ton vehicule detecte cette condition, il enregistre P0380 et allume le voyant moteur.

Quels sont les symptomes de P0380 ?

Si ton vehicule a declenche P0380, tu peux remarquer un ou plusieurs de ces symptomes :

  • Check engine light or glow plug indicator illuminated
  • Hard or extended cranking when starting cold
  • White or grey smoke from the exhaust on cold start
  • Rough idle and misfire for the first minute after a cold start
  • Reduced cold-weather startability, worse as temperatures drop
  • Will likely fail a diesel emissions or technical inspection

Quelles sont les causes de P0380 ?

Voici les causes les plus courantes de P0380, classees selon la probabilite qu'elles soient en cause :

eleveeFailed glow plug relay or glow plug control module
eleveeOne or more failed glow plugs (open circuit)
moyenneCorroded or broken wiring/connectors in the glow plug harness
moyenneBlown glow plug system fuse
faiblePoor ground connection to the glow plug circuit
faibleFaulty ECU glow plug driver output (rare)

Peut-on rouler sans risque avec P0380 ?

En general oui, pour des trajets courts. Safe to drive once the engine is warm. The glow plug system only assists cold starting on diesel engines, so the engine runs normally after warmup. Expect harder, longer cranking on cold mornings and more white smoke at startup. The car will likely fail a diesel inspection with this code stored.

Comment diagnostique-t-on P0380 ?

Suis ces etapes pour identifier la cause profonde de P0380 :

  1. Read the stored code and freeze frame with Skanyx or any ELM327 adapter to confirm P0380 and note the temperature at which it set
  2. Check the glow plug system fuse and relay first, as a blown fuse or failed relay sets this circuit-level code
  3. With the ignition off and glow plugs disconnected, bench-test each plug with a multimeter: a healthy glow plug reads roughly 0.5-2 ohm, while an open (infinite) reading means that plug has failed
  4. Inspect the glow plug harness and connectors for corrosion, broken pins, or chafed wiring
  5. Verify the relay/control module sends battery voltage to the plugs during the preheat cycle with a multimeter on the supply side
  6. Note that per-cylinder glow plug live status is manufacturer-extended (Mode $22) data and is not available over generic OBD2, so the multimeter bench test is how you find the specific failed plug

Combien coute la reparation de P0380 ?

Les couts de reparation de P0380 varient selon la cause profonde et ton vehicule. Voici des estimations courantes :

Reparation Cout des pieces Cout de main-d'oeuvre Estimation totale Difficulte en autonomie
Replace glow plug system fuse (DIY) €2–€8 €0–€0 €2–€8 Facile
Replace a single glow plug (DIY) €10–€30 €0–€0 €10–€30 Moderee
Replace glow plug relay/control module (shop) €40–€180 €50–€130 €90–€310 Moderee
Replace full glow plug set plus relay (shop) €80–€260 €90–€220 €170–€480 Professionnel

Prix estimes au March 2026. Les couts varient selon la region, le vehicule et le garage.

P0380 sur des vehicules specifiques

P0380 se comporte differemment selon ton vehicule. Selectionne ta voiture ci-dessous pour des causes propres au modele, les problemes connus et des estimations de couts ajustees :

Volkswagen

P0380 sur Volkswagen Golf TDI

2005-2021

The Golf TDI commonly sets P0380 from a failed glow plug control module or aged plugs around 120,000-180,000 km. On many TDI engines the glow plug controller is a smart module that monitors each plug, so a single open plug can flag the circuit. Access is reasonable but the plugs can seize if they have never been changed, so a workshop with proper extraction tools is recommended on high-mileage cars.

Quelles sont les causes de P0380 sur une Volkswagen Golf TDI ?

Volkswagen Golf TDIFailed glow plug control module on TDI engines
Volkswagen Golf TDISeized glow plugs on high-mileage cars that have never been serviced

Cout de reparation de P0380 pour Volkswagen Golf TDI

Couts estimes pour les proprietaires de Volkswagen Golf TDIajuste a la hausse par rapport a la moyenne en raison du prix des pieces specifiques a Volkswagen

Reparation Cout des pieces Cout de main-d'oeuvre Estimation totale Difficulte en autonomie
Replace glow plug system fuse (DIY) €2–€8 €0–€0 €2–€8 Facile
Replace a single glow plug (DIY) €11–€32 €0–€0 €11–€32 Moderee
Replace glow plug relay/control module (shop) €42–€189 €53–€137 €95–€326 Moderee
Replace full glow plug set plus relay (shop) €84–€273 €95–€231 €179–€504 Professionnel

Prix estimes au March 2026. Les couts varient selon la region, le vehicule et le garage.

BMW

P0380 sur BMW 320d

2005-2019

BMW diesels (M47, N47, B47) use a glow plug control module that reports circuit faults. On the N47, access to the glow plugs is tight and seized plugs are common, which raises labor. P0380 here is usually the control module or aged plugs. Per-cylinder glow plug status on BMW lives on Mode $22 extended data and needs a BMW-specific tool such as Carly, not generic OBD2.

Quelles sont les causes de P0380 sur une BMW 320d ?

BMW 320dGlow plug control module failure on N47/B47 engines
BMW 320dSeized plugs increasing labor on tight N47 cylinder head access

Cout de reparation de P0380 pour BMW 320d

Couts estimes pour les proprietaires de BMW 320dajuste a la hausse par rapport a la moyenne en raison du prix des pieces specifiques a BMW

Reparation Cout des pieces Cout de main-d'oeuvre Estimation totale Difficulte en autonomie
Replace glow plug system fuse (DIY) €3–€11 €0–€0 €3–€11 Facile
Replace a single glow plug (DIY) €14–€41 €0–€0 €14–€41 Moderee
Replace glow plug relay/control module (shop) €54–€243 €68–€176 €122–€419 Moderee
Replace full glow plug set plus relay (shop) €108–€351 €122–€297 €230–€648 Professionnel

Prix estimes au March 2026. Les couts varient selon la region, le vehicule et le garage.

Audi

P0380 sur Audi A4 TDI

2004-2019

The A4 TDI shares VAG glow plug architecture with the Golf and uses a monitoring control module. P0380 typically points to the module or aged plugs at higher mileage. Some 2.0 and 3.0 TDI engines run ceramic glow plugs that are more fragile and snap if removed cold, so warm removal and care are important to avoid a far costlier head repair.

Quelles sont les causes de P0380 sur une Audi A4 TDI ?

Audi A4 TDIGlow plug control module fault on VAG TDI engines
Audi A4 TDIFragile ceramic glow plugs snapping during removal on some 2.0/3.0 TDI

Cout de reparation de P0380 pour Audi A4 TDI

Couts estimes pour les proprietaires de Audi A4 TDIajuste a la hausse par rapport a la moyenne en raison du prix des pieces specifiques a Audi

Reparation Cout des pieces Cout de main-d'oeuvre Estimation totale Difficulte en autonomie
Replace glow plug system fuse (DIY) €2–€9 €0–€0 €2–€9 Facile
Replace a single glow plug (DIY) €12–€35 €0–€0 €12–€35 Moderee
Replace glow plug relay/control module (shop) €46–€207 €57–€150 €103–€357 Moderee
Replace full glow plug set plus relay (shop) €92–€299 €103–€253 €195–€552 Professionnel

Prix estimes au March 2026. Les couts varient selon la region, le vehicule et le garage.

Mercedes-Benz

P0380 sur Mercedes-Benz (OM651 diesel)

2008-2018

The OM651 four-cylinder diesel uses a glow plug control module that the ECU monitors for circuit faults. P0380 on the OM651 is commonly the module or worn plugs. Mercedes glow plug data beyond the generic circuit code is manufacturer-extended and needs XENTRY or a Mercedes-capable tool. Plug access is moderate but the plugs can seize on neglected engines.

Quelles sont les causes de P0380 sur une Mercedes-Benz (OM651 diesel) ?

Mercedes-Benz (OM651 diesel)Glow plug control module failure on OM651
Mercedes-Benz (OM651 diesel)Worn or seized plugs on neglected high-mileage engines

Cout de reparation de P0380 pour Mercedes-Benz (OM651 diesel)

Couts estimes pour les proprietaires de Mercedes-Benz (OM651 diesel)ajuste a la hausse par rapport a la moyenne en raison du prix des pieces specifiques a Mercedes-Benz

Reparation Cout des pieces Cout de main-d'oeuvre Estimation totale Difficulte en autonomie
Replace glow plug system fuse (DIY) €3–€10 €0–€0 €3–€10 Facile
Replace a single glow plug (DIY) €13–€39 €0–€0 €13–€39 Moderee
Replace glow plug relay/control module (shop) €52–€234 €65–€169 €117–€403 Moderee
Replace full glow plug set plus relay (shop) €104–€338 €117–€286 €221–€624 Professionnel

Prix estimes au March 2026. Les couts varient selon la region, le vehicule et le garage.

Ces codes apparaissent souvent avec P0380 ou indiquent des problemes connexes :

Questions frequentes sur P0380

Can I drive with a P0380 code?

Yes. Glow plugs only help a cold diesel start, so once the engine is warm it runs normally. You will get harder cold starts, more startup smoke, and the car will likely fail inspection until the fault is fixed.

Will a bad glow plug stop my diesel from starting?

Usually not in mild weather. A warm engine or warm climate often starts fine with one or two dead glow plugs. In cold weather, multiple failed plugs can cause long cranking, heavy white smoke, or a no-start.

How do I find which glow plug is bad?

Disconnect each plug and measure its resistance with a multimeter. A good glow plug reads about 0.5-2 ohm. A plug that reads open (no continuity) has failed. Generic OBD2 only gives you the circuit code, not per-plug status.

Is it worth replacing all glow plugs at once?

Often yes. Glow plugs age together and most of the labor is gaining access. If one has failed at high mileage, replacing the full set avoids a second job when the next plug fails soon after.

Why does my diesel smoke white on cold start with this code?

Without working glow plugs the cold combustion chambers cannot fully ignite the diesel, so unburned fuel leaves the exhaust as white smoke until the engine warms up. The smoke clears once the engine reaches operating temperature.

Lis nos guides detailles

Skanyx

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