OBD-II Code P0380 is defined as a Glow Plug/Heater Circuit “A” Malfunction. This trouble code is specific to diesel engines, where glow plugs are essential for heating the combustion chambers to facilitate a quick cold start.
What Does the P0380 Code Mean?
The P0380 code indicates that the Power Train Control Module (PCM) has detected a problem with the glow plug circuit. Specifically, this code sets when the PCM sees less than 4 volts output to the glow plugs when they should be energized or more than 4 volts when they should not be.
What Causes the P0380 Code?
Several issues can trigger the P0380 code, including:
- Malfunction of the Glow Plug Relay
- Malfunction of the Glow Plug Control Unit
- Defective Glow Plugs
- Defective wiring or connections in the Glow Plug wiring harness
What Are the Symptoms of the P0380 Code?
The symptoms associated with the P0380 code may include:
- Illumination of the Check Engine Light
- Failure of emissions inspections due to MIL malfunction
- Difficulty starting the vehicle
- In rare cases, no noticeable adverse conditions
How Serious Is the P0380 Code?
The P0380 code is considered urgent because it signifies significant malfunctions that can lead to severe damage to the vehicle or pose risks to the driver and passengers. Immediate action is recommended.
How to Diagnose the P0380 Code
To diagnose the P0380 code, follow these steps:
- Check the freeze frame data to understand when the malfunction occurred.
- Use a data streaming scan tool to monitor the output voltage to the glow plugs.
- Look for output voltage of over 4 volts when the glow plugs should be activated.
- Inspect and test the Glow Plug Relay and its wiring harness.
- If necessary, check the Glow Plug Control Unit for proper voltage drops and continuity.
Common Repairs for the P0380 Code
Common repairs associated with the P0380 code include:
- Replacing defective glow plugs
- Repairing or replacing the Glow Plug Relay
- Replacing the Glow Plug Control Unit
- Fixing wiring issues or connections in the Glow Plug harness
How Much Does It Cost to Fix the P0380 Code?
The cost to repair the P0380 code can vary widely based on the underlying issue. Simple repairs like replacing glow plugs may cost between $100 to $300, while more complex repairs involving the control unit or wiring may range from $300 to $600 or more, depending on labor rates and parts costs.
Can I Fix the P0380 Code Myself?
While some DIY enthusiasts may be able to handle simple repairs, diagnosing and fixing the P0380 code often requires specialized tools and knowledge. If you’re not confident in your abilities, it is advisable to seek professional assistance to ensure proper diagnosis and repair.
