P0380 on Mercedes-Benz
Glow Plug/Heater Circuit A Malfunction
P0380 on Mercedes-Benz vehicles indicates glow plug/heater circuit a malfunction. Au7o has documented this code across 1 Mercedes-Benz model — most commonly on Sprinter. P0380 applies to diesel engines and means the computer detected a malfunction in glow plug heater circuit 'A'. Glow plugs preheat the combustion chambers to help a cold diesel start, and the control module monitors the glow plug circuit (often through a relay/control module); when the current or voltage isn't what it expects, it sets this code. The most noticeable symptom is hard cold starting, rough running until warm, or extra white smoke at startup. It indicates an electrical fault in the glow plug system rather than a fuel-injection problem. Typical repair costs on Mercedes-Benz range from $300 to $1,500, depending on the specific model and root cause.
Common Causes of P0380
- •One or more failed glow plugs
- •Faulty glow plug control module or relay
- •Corroded or loose glow plug wiring/connectors
- •Open or shorted glow plug circuit wiring
- •Blown glow plug fuse
- •Poor power feed or ground to the glow plug circuit
- •Failed driver in the engine control module
P0380 on Mercedes-Benz by Model
Mercedes-Benz Sprinter(1 issue)
- Glow Plug Failure and Cold Start Issues2007-2025
Sprinter glow plugs fail with age, causing hard starting in cold weather, rough idle when cold, and white smoke on startup. The OM642 V6 is particularly prone to glow plug seizure in the cylinder head, making removal difficult and risking broken glow plugs that require cylinder head removal to extract.
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View P0380 across all makes →Frequently Asked Questions
What does P0380 mean on Mercedes-Benz?▼
P0380 stands for "Glow Plug/Heater Circuit A Malfunction." P0380 applies to diesel engines and means the computer detected a malfunction in glow plug heater circuit 'A'. Glow plugs preheat the combustion chambers to help a cold diesel start, and the control module monitors the glow plug circuit (often through a relay/control module); when the current or voltage isn't what it expects, it sets this code. The most noticeable symptom is hard cold starting, rough running until warm, or extra white smoke at startup. It indicates an electrical fault in the glow plug system rather than a fuel-injection problem. On Mercedes-Benz specifically, this code is documented across 1 model.
What causes P0380 on Mercedes-Benz vehicles?▼
Common causes on Mercedes-Benz: One or more failed glow plugs, Faulty glow plug control module or relay, Corroded or loose glow plug wiring/connectors, Open or shorted glow plug circuit wiring, Blown glow plug fuse. Specific causes vary by model and year — see the per-model sections below.
How much does it cost to fix P0380 on a Mercedes-Benz?▼
Repair costs on Mercedes-Benz range from $300 to $1,500, depending on the specific model and root cause.
Which Mercedes-Benz models have P0380 documented?▼
Au7o has documented P0380 on 1 Mercedes-Benz model: Sprinter.