P0671 Fault Code

Cylinder 1 Glow Plug Circuit

• What does that mean?
• Symptoms
• Causes
• Solutions

The P0671 code indicates a malfunction in the glow plug circuit for Cylinder 1 in a diesel engine. The glow plugs are vital for starting the engine, especially in cold temperatures, as they preheat the air in the combustion chamber. If there's an issue with the circuit connected to the glow plug, it can lead to poor engine performance and starting difficulties.

What are the symptoms of the P0671 code?

When the P0671 code is triggered, you may experience:

• Difficulty starting the engine, especially in cold weather
• Rough idling or misfiring
• Decreased fuel efficiency
• Illuminated check engine light on the dashboard.

What causes the P0671 code?

Several factors can cause a P0671 code, including:

• A faulty glow plug in Cylinder 1
• Issues with the glow plug control module
• Damaged wiring or connectors in the glow plug circuit
• A blown fuse related to the glow plug circuit
• Poor electrical connections or corrosion.

How to fix P0671?

To resolve the P0671 code, a mechanic may:

• Inspect and test the glow plug for Cylinder 1, replacing it if faulty
• Examine the wiring and connectors for signs of wear or damage, repairing or replacing as needed
• Check the glow plug control module for proper operation
• Ensure all electrical connections are clean and secure
• If necessary, replace any blown fuses associated with the glow plug circuit.