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DTC P0126: Notes

DTC P0126 DETECTION & CONDITION POSSIBLE CAUSES

DTC P0126 Insufficient coolant temperature for stable operation
DETECTION CONDITION 
  • The PCM monitors the ECT after the engine start for a certain period. If the ECT never exceeds 71 °C {160 °F}  when the following conditions are met, the PCM determines that the coolant thermostat is stuck open.

MONITORING CONDITIONS 
  • ECT at engine start: less than 51 °C {123 °F} 
  • Estimated ambient temperature: more than -10 °C {14 °F} 

Diagnostic support note 
  • This is a continuous monitor (Thermostat).
  • The MIL illuminates if the PCM detects the above malfunction condition in two consecutive drive cycles or in one drive cycle while the DTC for the same malfunction has been stored in the PCM.
  • PENDING CODE is available if the PCM detects the above malfunction condition during the first drive cycle.
  • FREEZE FRAME DATA is available.
  • The DTC is stored in the PCM memory.
POSSIBLE CAUSE 
  • Coolant thermostat malfunction
  • VSS malfunction
  • IAT sensor malfunction
  • ECT sensor malfunction
  • PCM malfunction