P0381 Fault Code

P0381 OBD-II Trouble Code Short Description

Glow Plug/Heater Indicator Circuit Malfunction

What does trouble code P0381 mean?

The P0381 fault code indicates a malfunction within the glow plug or heater indicator circuit. This is typical in diesel engines where glow plugs assist in starting the engine under cold conditions. When this circuit is faulty, the engine may struggle to start, especially in colder temperatures.

Symptoms

What are the symptoms of the P0381 code?

  • Difficulty starting the engine in cold weather
  • Check Engine Light (CEL) illuminated
  • Possibly reduced engine performance
  • Increased emissions during startup

Causes

What causes the P0381 code?

  • Faulty glow plugs
  • Defective glow plug relay
  • Open or short circuit in the wiring
  • Malfunctioning engine control module (ECM)
  • Poor electrical connections in the circuit

Possible Solutions

How to fix P0381?

  • Inspect and test glow plugs for functionality
  • Check the glow plug relay for proper operation
  • Examine wiring for any signs of damage or corrosion
  • Repair or replace any faulty components found during inspection
  • Reset the fault code and test drive the vehicle to verify repair