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Home >> Mazda >> 2021 >> 3 Base >> Repair and Diagnosis >> Engine Performance >> System >> Symptom Troubleshooting - Engine (VINS 7, L, M) >> Cooling System Concerns-Runs Cold >> Notes
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Cooling System Concerns-Runs Cold: Notes

COOLING SYSTEM CONCERNS-RUNS COLD (VINs 7, L, M) DESCRIPTION AND POSSIBLE CAUSE

Troubleshooting item Cooling system concerns-runs cold
Description
  • Engine does not reach normal operating temperature.
Possible cause
  • ECT sensor No. 1 malfunction (value higher than actual engine coolant temperature detected)
  • ECT sensor No. 2 malfunction (value higher than actual engine coolant temperature detected)
  • Cooling fan system malfunction
  • Thermostat malfunction (stuck at fully open) (built-into coolant control valve)
  • Active air shutter malfunction (With active air shutter)
System wiring diagram
  • Not applicable
Connector diagram
  • Not applicable