DEF FAULT CODES

UnclassifiedFuel

What This Code Means

Derate warning; Power derate; Hard starting; Loss of power; No-crank; Regen warning light; Restricted exhaust; Progressive power derate; Regen warning; Reduced power; Excessive smoke; Turbo whine; Injector fouling; Filter clogging

Possible Causes

  • DEF system (SCR) failure
  • Fuel filters failure
  • Battery failure due to extended storage
  • DPF regeneration failure
  • DPF (Diesel Particulate Filter) failure
  • Turbocharger failure
  • Poor fuel quality
  • Sustained high load

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