P0380 OBD-II Trouble Code: Glow Plug/Heater Circuit “A” Malfunction

Our certified mechanics come to you · Get a fair and transparent estimate upfront

Red-stars EXCELLENT RATING ON

Cost of diagnosing the P0380 code

P0380 is a diagnostic trouble code (DTC) for "Glow Plug/Heater Circuit “A” Malfunction". This can happen for multiple reasons and a mechanic needs to diagnose the specific cause for this code to be triggered in your situation. Our certified mobile mechanics can come to your home or office to perform the Check Engine Light diagnostic for $114.99 . Once we are able to diagnose the problem, you will be provided with an upfront quote for the recommended fix and receive $20.0 off as a credit towards the repair. All our repairs are backed by our 12-month / 12,000-mile warranty.

Cars Estimate Credit towards follow-up repair Earliest Availability
Ford $114.99 $20.0
Toyota $114.99 $20.0
BMW $124.99 $20.0
SCHEDULE P0380 DIAGNOSTIC Get a fair and transparent estimate upfront

P0380 code definition

The P0380 trouble code notes an issue with the glow plug heater circuit A.

What the P0380 code means

The P0380 code is a standard OBD-II trouble code suggesting an issue within the glow plug heater circuit. When the powertrain control module (PCM) detects a variation in the voltage from the “A” area of the glow plug heater circuit that is more than a 10 percent variation from the expected output, the P0380 code will be detected. This code is associated with numerous other glow plug trouble codes.

What causes the P0380 code?

Many things can trigger the P0380 code. Some of the more common issues include:

  • Malfunctioning glow plug or relay
  • Faulty glow plug timer
  • Faulty glow plug module
  • Blown fuse in the circuit
  • Faulty wiring and electrical connectors, such as corroded connectors or open wiring

What are the symptoms of the P0380 code?

When the P0380 trouble code is triggered, it will likely be accompanied by the check engine soon Warning Light, as well as the globe plug indicator Warning Light. The vehicle also may have a difficult time starting, may be excessively noisy during start-up, and may produce white exhaust smoke.

How does a mechanic diagnose the P0380 code?

The P0380 code will be diagnosed using a standard OBD-II trouble code scanner. A professional mechanic will use the scanner to observe the freeze frame data. Using the freeze frame data, the mechanic can learn more about the P0380 code, and search for additional codes (it is common for the P0380 code to be accompanied by other glow plug trouble codes). The technician will then reset the trouble codes and restart the vehicle, to see if the codes return. If the codes do not return, it is assumed that they are intermittent and that the glow plug heater circuit is in working order.

If the P0380 code returns, the mechanic should inspect the wires, connectors, and fuses around the glow plug heater circuit. Any loose or open wires, corroded or damaged connectors, or blown fuses should be replaced. Following replacement, the trouble codes should once again be reset, and the vehicle restarted, to see if the issue has been resolved. If it has not, the mechanic will remove the glow plug in the A area and test it, as well as the relay. If needed, the components will be replaced, and all remaining trouble codes should be addressed as well.

Common mistakes when diagnosing the P0380 code

The most common mistake when diagnosing the P0380 code comes from a failure to properly follow the OBD-II trouble code diagnosis protocol. Mechanics should always follow the proper protocol in order, which includes addressing numerous trouble codes in the order in which they appear.

Failure to follow the proper protocol can also result in the glow plug or relay being replaced when the wires, connectors, or fuses were the actual issue.

How serious is the P0380 code?

A detected P0380 code is unlikely to render a vehicle as unable to operate, but it will keep the engine from running properly.

What repairs can fix the P0380 code?

The most common repairs for the P0380 trouble code include:

  • Replacement of a glow plug or glow plug relay
  • Replacement of heater circuit wires, connectors, and fuses
  • Replacement of glow plug timer or module

Additional comments for consideration regarding the P0380 code

While blown fuses in the glow plug heater circuit are commonly associated with the P0380 code, they are usually the result of a deeper issue. If a blown fuse is detected, it should be replaced, but it shouldn’t be assumed to be the only issue or the cause of the P0380 trouble code.

Need help with a P0380 code?

YourMechanic offers certified mobile mechanics who will come to your home or office to diagnose and repair your vehicle. Get a quote and book an appointment online or speak to a service advisor at 1-800-701-6230.

Check Engine Light
trouble codes
P0380

No more waiting rooms! Our mechanics will come to you to diagnose and fix the P0380 code.

SCHEDULE P0380 DIAGNOSTIC
Get a $20 credit for the follow-up repair

Recent Check Engine Light is on Inspection reviews

Excellent Rating

(7400)

Rating Summary
6879
249
58
41
173
6879
249
58
41
173
 at YourMechanic

David

13 years of experience
393 reviews
David
13 years of experience
Chevrolet Malibu L4-2.4L - Check Engine Light is on Inspection - Marietta, Georgia
He explained everything to me in detail on what I needed to know about my car. Definitely recommend him for getting the job done.
 at YourMechanic

Raymond

37 years of experience
402 reviews
Raymond
37 years of experience
Toyota Camry L4-2.2L - Check Engine Light is on - Las Vegas, Nevada
Raymond did a great job however I was charged for two hours labor and he was only here less than 45 minutes. should I expect this on future appointments with your mechanic ?
 at YourMechanic

Shane

17 years of experience
217 reviews
Shane
17 years of experience
Volkswagen EuroVan V6-2.8L - Check Engine Light is on Inspection - Austin, Texas
Arrived on time. Explained the issues he found and how he will fix it. I have parts on order and will schedule an appointment to have Shane install the parts when they arrive.
 at YourMechanic

Kanstantsin

19 years of experience
51 reviews
Kanstantsin
19 years of experience
Ford F-150 V8-4.6L - Check Engine Light is on Inspection - Littleton, Colorado
Kanstantsin arrived early. Was very courteous and professional. Will highly recommend to anyone. Thank you Kanstantsin.


More related articles

P2317 OBD-II Trouble Code: Ignition Coil F Secondary Circuit
P2317 P2317 code definition Ignition coil F secondary circuit What the P2317 code means This trouble code indicates that the powertrain control module has detected an abnormal reference voltage from the one of the engine’s ignition coils. What are the...
P2779 OBD-II Trouble Code: Downshift Switch Circuit Range/Performance
P2779 means a problem with the downshift switch circuit usually caused by liquid that has spilled on the switch or other electrical issues.
P0579 OBD-II Trouble Code: Cruise Control Multi-Function Input A Circuit Range/Performance
P0579 P0579 OBD-II Trouble Code: Cruise Control Multi-Function Input A Circuit Range/Performance P0579 code definition The P0579 code signifies that the car’s computer has found a malfunction in the cruise control multi-function input A circuit. What the P0579 code means...

Related questions

P0421 comes up on scan. What is the likely culprit
Hello. When you get the P0421 code (https://www.yourmechanic.com/article/p0421-obd-ii-trouble-code-warm-up-catalyst-efficiency-below-threshold-bank-1-by-andrew-quinn), it usually means that you have a failing catalytic converter (https://www.yourmechanic.com/services/catalytic-converter-replacement). It is very common for converters to fail on this vehicle over time. Most of the time I use a scan...
Check Engine Light is on and I've noticed one minute my gas says a half a tank and the next it's at a quarter
Hello. This is most likely a faulty fuel sending unit (https://www.yourmechanic.com/services/fuel-gauge-sender-replacement). This is a unit that sits in the fuel tank that sends a signal relaying how much fuel is in the tank. These commonly go bad on many cars....
Engine running rough - 2001 Ford F-150
Hi there. Have the codes returned since the repair? It sounds like the valve timing control valves are sticking. The valve timing control valves control oil flow to the valve timing actuator and are a duty cycle type controller. The...

How can we help?

Our service team is available 7 days a week, Monday - Friday from 6 AM to 5 PM PST, Saturday - Sunday 7 AM - 4 PM PST.

1 (855) 347-2779 · hi@yourmechanic.com