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Diagnostic Procedure

COOLING SYSTEM CONCERNS - OVERHEATING (SKYACTIV-G, US) DIAGNOSTIC PROCEDURE

Step Inspection Results Action
1 INSPECT VEHICLE CONDITION FOR EFFECT ON MALFUNCTION
  • Verify how the customer drives the vehicle by asking the customer the following:
    • Engine speed is high and remains high for continuous long periods like when climbing a long, steep grade.
  • Is the engine generating excessive heat when driven?
Yes Explain to the customer that the vehicle is normal and give them advice how to use vehicle and provide a specific example of the conditions in which the engine overheats.
No Go to the next step.
2 VERIFY PCM DTC
  • Perform the DTC inspection for the PCM. (See DTC INSPECTION .)
  • Are any DTCs displayed?
Yes Repair the malfunctioning location according to the applicable DTC troubleshooting.
(See DTC TABLE [PCM (SKYACTIV-G (US))] .)
No Go to the next step.
3 DETERMINE IF MALFUNCTION CAUSE IS A/C SYSTEM OR OTHER
  • Start the engine and run it at idle speed.
  • Turn the A/C switch off.
  • Does the A/C compressor disengaged?
Yes Go to the next step.
No Perform the symptom troubleshooting "A/C IS ALWAYS ON OR A/C COMPRESSOR RUNS CONTINUOUSLY".
(See A/C IS ALWAYS ON OR A/C COMPRESSOR RUNS CONTINUOUSLY .)
4 INSPECT ECT SENSOR No. 1 SIGNAL
  • Access the ECT PID using the MMDS. (See PID/DATA MONITOR INSPECTION .)
  • Compare the ECT PID and high engine coolant temperature warning indication operation.
  • Is the ECT PID value same as warning indication readings
Yes Go to Step 6.
No Go to the next step.
5 INSPECT ECT SENSOR No. 1 FOR MALFUNCTION
Yes Inspect the body control module (BCM).
(See BODY CONTROL MODULE (BCM) INSPECTION [(US)] .)
No Repair or replace the malfunctioning location and perform the repair completion verification.
(See ENGINE COOLANT TEMPERATURE (ECT) SENSOR REMOVAL/INSTALLATION [SKYACTIV-G (VIN M (US))] .)
(See ENGINE COOLANT TEMPERATURE (ECT) SENSOR REMOVAL/INSTALLATION [SKYACTIV-G (VIN L (US))] .)
6 INSPECT ECT SENSOR No. 2 SIGNAL
  • Access the ECT2 PID using the MMDS. (See PID/DATA MONITOR INSPECTION .)
  • Compare the ECT2 PID and high engine coolant temperature warning indication operation.
  • Is the ECT2 PID value same as warning indication readings
Yes Go to Step 8.
No Go to the next step.
7 INSPECT ECT SENSOR No. 2 FOR MALFUNCTION
Yes Inspect the body control module (BCM).
(See BODY CONTROL MODULE (BCM) INSPECTION [(US)] .)
No Repair or replace the malfunctioning location and perform the repair completion verification.
(See ENGINE COOLANT TEMPERATURE (ECT) SENSOR REMOVAL/INSTALLATION [SKYACTIV-G (VIN M (US))] .)
(See ENGINE COOLANT TEMPERATURE (ECT) SENSOR REMOVAL/INSTALLATION [SKYACTIV-G (VIN L (US))] .)
8 INSPECT COOLANT CONTROL VALVE FOR MALFUNCTION
Yes Go to the next step.
No Repair or replace the malfunctioning location and perform the repair completion verification.
(See COOLANT CONTROL VALVE REMOVAL/INSTALLATION [SKYACTIV-G (VIN M (US))] .)
(See COOLANT CONTROL VALVE REMOVAL/INSTALLATION [SKYACTIV-G (VIN L (US))] .)
9 INSPECT COOLING FAN CONTROL SYSTEM OPERATION
Yes Vehicles with active air shutter:
  • Go to the next step.

Vehicles without active air shutter:
  • Go to Step 11.
No Repair or replace the malfunctioning location and perform the repair completion verification.
10 INSPECT ACTIVE AIR SHUTTER FOR MALFUNCTION
Yes Go to the next step.
No Repair or replace the malfunctioning location and perform the repair completion verification.
(See ACTIVE AIR SHUTTER REMOVAL/INSTALLATION .)
11 INSPECT COOLING SYSTEM CAP FOR MALFUNCTION
Yes Go to the next step.
No Repair or replace the malfunctioning location and perform the repair completion verification.
12 INSPECT RELATED PART CONDITION
  • Inspect the following:
    • Engine coolant performance
    • Coolant leakage (engine internal, external)
    • Water and anti-freeze mixture
    • Fuses
    • Inappropriate engine coolant concentration (engine coolant in radiator freezes and engine coolant does not flow)
      • Foreign matter penetration in engine coolant
  • Is there any malfunction?
Yes Repair or replace the malfunctioning location and perform the repair completion verification.
No Go to the next step.
13 VERIFY IF MALFUNCTION CAUSED BY LACK OF ENGINE COOLANT
Yes Add engine coolant and verify that there is no engine coolant leakage. (See ENGINE COOLANT REPLACEMENT [SKYACTIV-G (VIN M (US))] .) (See ENGINE COOLANT REPLACEMENT [SKYACTIV-G (VIN L (US))] .)
(See ENGINE COOLANT LEAKAGE INSPECTION [SKYACTIV-G (VIN M (US))] .) (See ENGINE COOLANT LEAKAGE INSPECTION [SKYACTIV-G (VIN L (US))] .)
  • If there is any malfunction:
    • Repair or replace the malfunctioning location and perform the repair completion verification.
No Go to the next step.
14 INSPECT DRIVE BELT
Yes Go to the next step.
No Replace the drive belt and perform the repair completion verification.
(See DRIVE BELT REMOVAL/INSTALLATION [SKYACTIV-G (VIN M (US))] .)
(See DRIVE BELT REMOVAL/INSTALLATION [SKYACTIV-G (VIN L (US))] .)
15 INSPECT RADIATOR FOR CLOGGING
  • Inspect for clogging in the radiator.
  • Is there any malfunction?
Yes Repair or replace the malfunctioning location and perform the repair completion verification.
No Replace the engine coolant and perform the repair completion verification.
(See ENGINE COOLANT REPLACEMENT [SKYACTIV-G (VIN M (US))] .)
(See ENGINE COOLANT REPLACEMENT [SKYACTIV-G (VIN L (US))] .)
Repair completion verification 1 VERIFY THAT VEHICLE IS REPAIRED
  • Install/connect the part removed/disconnected during the troubleshooting procedure.
  • Has the malfunction symptom been eliminated?
Yes Complete the symptom troubleshooting. (Explain contents of repair to customer)
No Refer to the controller area network (CAN) malfunction diagnosis flow to inspect for a CAN communication error.
(See CONTROLLER AREA NETWORK (CAN) MALFUNCTION DIAGNOSIS FLOW [(US)] .)
  • If the CAN communication is normal, perform the diagnosis from Step 1.
    • If the malfunction recurs, go to the next step.
Repair completion verification 2 VERIFY IF MALFUNCTION IS CAUSED BY NOT PERFORMING PCM REPROGRAMMING
  • Verify repair information and verify that there is a new calibration in the PCM.
  • Is there a new calibration in the PCM?
Yes Perform the PCM reprogramming and verify if the malfunction symptom was corrected.
No Replace the PCM. (See PCM REMOVAL/INSTALLATION [SKYACTIV-G (VIN M (US))] .) (See PCM REMOVAL/INSTALLATION [SKYACTIV-G (VIN L (US))] .)