NO.18 COOLING SYSTEM CONCERNS-RUNS COLD [WL-C, WE-C]

id0103b6802400

18

COOLING SYSTEM CONCERNS-RUNS COLD

DESCRIPTION

•  Engine takes excessive period of time to reach normal operating temperature.

POSSIBLE CAUSE

•  Thermostat malfunction

•  Cooling fan system malfunction

•  Coolant heater system malfunction

18	COOLING SYSTEM CONCERNS-RUNS COLD
DESCRIPTION	• Engine takes excessive period of time to reach normal operating temperature.
POSSIBLE CAUSE	• Thermostat malfunction • Cooling fan system malfunction • Coolant heater system malfunction

Diagnostic Procedure

STEP	INSPECTION	RESULTS	ACTION
1	Is the customer complaint “Lack of passenger compartment heat”?	Yes	Inspect the A/C heater system.
1		No	Go to the next step.
2	Does the engine speed continue at fast idle?	Yes	Go to the symptom troubleshooting “NO.7 SLOW RETURN TO IDLE [WL-C, WE-C]”.
2	Does the engine speed continue at fast idle?	No	Go to the next step.
3	Remove the thermostat and inspect the operation. (See THERMOSTAT REMOVAL/INSTALLATION [WL-C, WE-C].) (See THERMOSTAT INSPECTION [WL-C, WE-C].) Is the thermostat normal?	Yes	Go to the next step.
3		No	Replace the thermostat.
4	Verify test results. • If normal, return to the diagnostic index to service any additional symptoms. (See SYMPTOM DIAGNOSTIC INDEX [WL-C, WE-C].) • If the malfunction remains, inspect the related Service Information and perform repair or diagnosis. ― If the vehicle is repaired, troubleshooting completed. ― If the vehicle is not repaired or additional diagnostic information is not available, reprogram the PCM if later calibration is available. Retest.