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No. 18 Cooling System Concerns-Runs Cold: Notes

NO. 18 COOLING SYSTEM CONCERNS-RUNS COLD DESCRIPTION AND POSSIBLE CAUSES (SKYACTIV-G 2.0, SKYACTIV-G 2.5)

18  COOLING SYSTEM CONCERNS-RUNS COLD 
DESCRIPTION 
  • Engine does not reach normal operating temperature.
POSSIBLE CAUSE 
  • Improper indication of low engine coolant temperature indicator light and/or high engine coolant temperature warning light
    • ECT sensor No. 1 malfunction
    • Instrument cluster malfunction
  • Cooling fan system malfunction
  • Condenser fan system malfunction
  • Thermostat malfunction (stuck at fully open)
  • Foreign matter penetration in engine coolant
CAUTION:
  • Verify the malfunction symptom according to not only the PID value but also the symptom troubleshooting.
RELATED PIDS

Item (definition) Unit/Condition Definition Condition/Specification (Reference)
ECT °C, °F Engine coolant temperature
  • Displays ECT
V ECT sensor No. 1 voltage
  • ECT is 20 °C {68 °F}: Approx. 3.10 V
  • ECT is 40 °C {104 °F}: Approx. 2.16 V
  • ECT is 60 °C {140 °F}: Approx. 1.40 V
  • ECT is 80 °C {176 °F}: Approx. 0.87 V
  • ECT is 100 °C {212 °F}: Approx. 0.54 V
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