Error code

OBD2 P0671

OBD2P0671
Diagnostic Trouble Code· Standard OBD-II fault code read from the vehicle's onboard diagnostics.

What it means

Cylinder 1 Glow Plug Circuit.

Severity

moderateCan drive, but starting issues may occur especially when cold

Summary

P0671 indicates an issue with the glow plug circuit for cylinder 1 in diesel engines. This code is set when there's a malfunction or open circuit detected by the PCM.

Symptoms

  • Engine difficulty starting, especially in cold weather
  • Check engine light illuminated

Common Causes

  • Defective glow plug on cylinder 1
  • Damaged wiring or connectors in the glow plug control circuit
  • Faulty relay or timer for older systems
  • Failed glow plug control module
  • Corroded or disconnected connections

Diagnosis

  1. Inspect wiring and connectors in the glow plug circuit
  2. Check for corrosion or damage on the glow plug lead
  3. Test the glow plug control module

Fixes

  • Replace faulty glow plug

FAQ

What causes P0671?

Common causes include a defective glow plug, damaged wiring or connectors, and issues with the relay or control module.

Not affiliated with OBD2. Answer summarized from the manufacturer's manual linked above; consult that source for the authoritative procedure.