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Home >> Mazda >> 2020 >> CX-30 Base, FWD >> Repair and Diagnosis >> Engine Performance >> System >> Symptom Troubleshooting - Engine >> Cooling System Concerns-Overheating (Us) >> Notes
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Cooling System Concerns-Overheating (Us): Notes

COOLING SYSTEM CONCERNS - OVERHEATING (SKYACTIV-G, US) DESCRIPTION AND POSSIBLE CAUSE

Troubleshooting item Cooling system concerns-overheating
Description
  • The engine coolant temperature is abnormally high.
Possible cause
  • Engine heat generation amount is excessive
    • Engine speed is high and remains high for continuous long periods
  • PCM DTC is stored
  • Improper operation of A/C system
  • Insufficient air blow volume
    • Cooling fan inoperative
    • Active air shutter is fully-closed and does not operate (With active air shutter)
    • Fan rotation speed decreases (such as generator malfunction) due to battery voltage decrease
    • ECT sensor No. 1 malfunction (value lower than actual engine coolant temperature detected)
      • ECT sensor No. 2 malfunction (value lower than actual engine coolant temperature detected)
  • Cooling system cap malfunction
  • Cooling fan motor assembly malfunction
  • Cooling fan motor connector malfunction
  • Active air shutter malfunction (With active air shutter)
  • Improper indication of high engine coolant temperature warning indication
    • ECT sensor No. 1 signal malfunction
    • ECT sensor No. 2 signal malfunction
    • Center display malfunction
    • Body control module (BCM) malfunction
      • Multi-information display malfunction
      • Blown fuse
  • Engine coolant system malfunction
    • Improper engine coolant level
      • Water pump malfunction
    • Engine coolant performance deterioration
    • Coolant leakage (engine internal, external)
    • Improper water/anti-freeze mixture
    • Improper operation of coolant control valve
    • Radiator malfunction (clogging)
    • Inappropriate engine coolant concentration (engine coolant in radiator freezes and engine coolant does not flow)
      • Foreign matter penetration in engine coolant
  • Leakage around heater unit in passenger compartment
  • Drive belt damage
System wiring diagram
  • Not applicable
Connector diagram
  • Not applicable