NO.22 COOLING SYSTEM CONCERNS-OVERHEATING [SKYACTIV-D 1.5]

id0103q2898900

22	COOLING SYSTEM CONCERNS-OVERHEATING
DESCRIPTION	•  The engine coolant temperature is abnormally high.
POSSIBLE CAUSE	•  PCM DTC is stored. •  Erratic signal to PCM ―  ECT sensor or related circuit malfunction •  A/C relay malfunction •  Fan control module malfunction •  Cooling system malfunction ―  Cooling fan motor malfunction ―  Coolant control valve malfunction ―  Engine coolant passage (including radiator) malfunction (clogging, leakage)

Diagnostic Procedure

STEP	INSPECTION	RESULTS	ACTION
1	VERIFY PCM DTC •  Retrieve PCM DTCs using the M-MDS. (See ON-BOARD DIAGNOSTIC TEST [SKYACTIV-D 1.5].) •  Are any DTCs present?	Yes	Go to the applicable DTC inspection. (See DTC TABLE [SKYACTIV-D 1.5].)
		No	Go to the next step.
2	VERIFY CURRENT INPUT SIGNAL STATUS Caution •  While performing this step, always operate the vehicle in a safe and lawful manner. •  When the M-MDS is used to observe monitor system status while driving, be sure to have another technician with you, or record the data in the M-MDS using the PID/DATA MONITOR AND RECORD capturing function and inspect later. •  Access the following PID using the M-MDS: (See ON-BOARD DIAGNOSTIC TEST [SKYACTIV-D 1.5].) ―  ECT •  Does the PID indicate the correct value under the trouble condition? (See PCM INSPECTION [SKYACTIV-D 1.5].)	Yes	Inspect the related sensor and circuit. •  If there is any malfunction: ―  Repair or replace the malfunctioning part according to the inspection results, then go to Step 9. •  If there is no malfunction: ―  Go to the next step.
		No	Go to the next step.
3	INSPECT A/C RELAY •  Switch the ignition off. •  Remove the A/C relay. •  Inspect the A/C relay. (See RELAY INSPECTION.) •  Is the A/C relay normal?	Yes	Go to the next step.
		No	Replace the A/C relay, then go to Step 9.
4	INSPECT FAN CONTROL MODULE •  Inspect the fan control module. (See FAN CONTROL MODULE INSPECTION [SKYACTIV-D 1.5].) •  Is the fan control module normal?	Yes	Go to the next step.
		No	Replace the fan control module, then go to Step 9. (See COOLING FAN MOTOR REMOVAL/INSTALLATION [SKYACTIV-D 1.5].)
5	INSPECT COOLING FAN MOTOR •  Inspect the cooling fan motor. (See COOLING FAN MOTOR INSPECTION [SKYACTIV-D 1.5].) •  Is the cooling fan motor normal?	Yes	Go to the next step.
		No	Replace the cooling fan motor, then go to Step 9. (See COOLING FAN MOTOR REMOVAL/INSTALLATION [SKYACTIV-D 1.5].)
6	DETERMINE IF MALFUNCTION CAUSE IS COOLANT CONTROL VALVE OR OTHER •  Verify the radiator hose tension. Warning •  To prevent burns, use a cloth with your hand to verify the tension of the radiator hose. •  After the engine warms up, does the engine coolant circulate to the radiator hose?	Yes	Go to Step 8.
		No	Go to the next step.
7	INSPECT COOLANT CONTROL VALVE •  Inspect the coolant control valve. (See COOLANT CONTROL VALVE INSPECTION [SKYACTIV-D 1.5].) •  Is the coolant control valve normal?	Yes	Go to the next step.
		No	Replace the coolant control valve, then go to Step 9. (See COOLANT CONTROL VALVE REMOVAL/INSTALLATION [SKYACTIV-D 1.5].)
8	INSPECT SEALING OF ENGINE •  Verify that there is no engine coolant leakage. (See ENGINE COOLANT LEAKAGE INSPECTION [SKYACTIV-D 1.5].) •  Is the sealing of engine normal?	Yes	Inspect for clogging in the engine coolant passage. •  If there is any malfunction: ―  Repair or replace the malfunctioning part according to the inspection results, then go to the next step. •  If there is no malfunction: ―  Go to the next step.
		No	Repair or replace the malfunctioning part according to the inspection results, then go to the next step.
9	Verify the test results. •  If normal, return to the diagnostic index to service any additional symptoms. (See SYMPTOM DIAGNOSTIC INDEX [SKYACTIV-D 1.5].) •  If a malfunction remains, inspect the related Service Information and perform the repair or diagnosis. ―  If the vehicle is repaired, troubleshooting is completed. ―  If the vehicle is not repaired or additional diagnostic information is not available, replace the PCM. (See PCM REMOVAL/INSTALLATION [SKYACTIV-D 1.5].)