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Details On DTCs

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DETECTION CONDITION AND POSSIBLE CAUSE

DESCRIPTION Thermostat stuck open
DETECTION CONDITION Determination conditions
  • Actual engine coolant temperature does not exceed 71 °C {160 °F} even though the estimated engine coolant temperature after the engine is started exceeds 71 °C {160 °F}.
Preconditions
  • Difference between value (2) detected by ECT sensor No. 2 during malfunction determination and value detected by ECT sensor No. 2 at engine start is 13 °C {23 °F} or more
  • Engine coolant temperature at engine start: 52 °C {126 °F} or less(1)
  • IAT: -10-45 °C {14-113 °F}(1)
  • Vehicle speed: 140 km/h {87 mph} or less(1)
  • Engine speed: 5, 400 rpm or less(1)
  • Idle ratio: 50 % or less
  • The following DTCs are not detected:
  • Fuel system malfunction: P0171:00, P0172:00, P2096:00, P2097:00
  • ECT sensor No. 1 malfunction: P0117:00, P0118:00
    • MAF sensor malfunction: P0102:00, P0103:00
Drive cycle
  • 2
Self test type
  • CMDTC self test
Sensor used
  • Desired engine coolant temperature: intake air temperature (IAT sensor), engine speed (CKP sensor), charging efficiency
  • Actual engine coolant temperature: ECT sensor No. 1, ECT sensor No. 2
FAIL-SAFE FUNCTION
  • Not applicable
VEHICLE STATUS WHEN DTCs ARE OUTPUT
  • Illuminates check engine light.
  • Heating is ineffective after engine is started
POSSIBLE CAUSE
  • ECT sensor No. 1 malfunction
  • ECT sensor No. 2 malfunction
  • Poor assembly of ECT sensor No. 1
  • Poor assembly of ECT sensor No. 2
  • Poor assembly of engine coolant hose (engine coolant passage malfunction)
  • Poor engine coolant, leakage, or freezing
  • Use of unspecified engine coolant
  • Foreign matter caught in thermostat (foreign matter penetration in engine coolant)
  • Thermostat malfunction
  • PCM malfunction
(1) Value can be verified by displaying PIDs using M-MDS
(2) Uses the ECT sensor No. 1 actual temperature or the estimated temperature, whichever one reaches 71 °C {160 °F} first, as the detection determination value.