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No. 17 Cooling System Concerns-Overheating: Contents

17	COOLING SYSTEM CONCERNS-OVERHEATING
DESCRIPTION	Engine runs at higher than normal temperature/overheats.
TROUBLE AREA	Engine heat generation amount is excessive Engine speed is high and remains high for continuous long periods ECM DTC is stored Improper operation of A/C system Insufficient air blow volume Cooling fan inoperative Fan rotation speed decreases (such as generator malfunction) due to battery voltage decrease Cooling system cap malfunction Cooling fan motor assembly malfunction Cooling fan motor connector malfunction Improper indication of low engine coolant temperature indicator light and/or high engine coolant temperature warning light ECT sensor No. 1 malfunction Combination meter malfunction Blown fuse Engine coolant system malfunction Improper engine coolant level Engine coolant performance deterioration Coolant leakage (engine internal, external) Improper water/anti-freeze mixture Thermostat malfunction (not fully open) Radiator malfunction (clogging) Leakage around heater unit in passenger compartment Drive belt damage

NOTE:

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)
Engine coolant temperature	°C, °F	Engine coolant temperature	Displays ECT
Engine coolant temperature	V	ECT sensor No. 1 voltage	Ignition switched ON (engine off) ECT is 29°C {84°F}: Approx. 2.65 V ECT is 88°C {190°F}: Approx. 0.71 V