DTC P0126:00, P0128:00: Notes

• The PCM monitors detects based on following calculation with ECT sensor No. 2 and estimated ECT sensor No. 2* at judge timing. When the difference between ECT sensor No. 2 and the estimated ECT sensor No. 2 is at the set value or more, a malfunction is detected.

  *: Estimated ECT sensor No. 2 output value when it is determined that there is a thermostat-open malfunction.

  MONITORING CONDITIONS 

  • IAT: above -10 °C {14 °F} 
  • Vehicle speed: over 6.3 km/h {3.9 mph} 

P0128:00 

• The PCM monitors detects based on the following calculation with the ECT sensor No. 2 and estimated ECT sensor No. 2* at the judge timing. When the difference between ECT sensor No. 2 and estimated ECT sensor No. 2 is at the set value or more, a malfunction is detected.

  *: Estimated ECT sensor No. 2 output value when it is determined that there is a thermostat open malfunction.

  MONITORING CONDITIONS 

  • IAT: above -10 °C {14 °F} 
  • ECT at engine start: below 52 °C {126 °F} 

Diagnostic support note 

• This is an intermittent monitor (engine cooling system).
• 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 first drive cycle.
• FREEZE FRAME DATA (Mode 2)/Snapshot data is available.
• The DTC is stored in the PCM memory.

• Thermostat malfunction
• ECT sensor No. 1 malfunction
• ECT sensor No. 2 malfunction
• Cooling system malfunction
• PCM malfunction