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2004 FORD TAURUS
3.0L V6 Vulcan•FWD•AUTOMATIC•gas
2 active safety recalls on this vehicle — view recalls
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Repairs0Labor487Torque3354Fluid7DTC1721Battery1Maintenance0Recalls2
P0684moderate severityPowertrain

Glow Plug Control Module to PCM Communication Circuit Range/Performance

on 2004 Ford Taurus 3.0L V6 Vulcan · FWD

What this code means

The PCM detects an out-of-range or implausible signal in communication with the glow plug control module. Glow plug timing and operation may be incorrect.

Symptoms

  • Difficult cold starting
  • Glow plug light flashing
  • White exhaust smoke when cold

Common causes

  • Damaged communication wiring
  • Poor connector contact
  • Faulty glow plug control module
  • PCM software fault

Diagnostic steps

  1. Retrieve related fault codes
  2. Inspect and test communication wiring
  3. Check for correct reference voltage
  4. Test or replace glow plug module
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