No. 17 Cooling System Concerns-Overheating: Procedure

1. Verify how the customer drives the vehicle by asking the customer the following:
   1. Engine speed is high and remains high for continuous long periods like when climbing a long, steep grade.
2. Is the engine generating excessive heat when driven?

   Result

   Result
   Yes
   No

Result:  2

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. 

Result:  1

No 

See step  2

1. Retrieve any DTCs using the Techstream.

   Refer to ON-BOARD DIAGNOSTIC TEST

2. Are any DTCs present?

   Result

   Result
   Yes
   No

Result:  2

Yes 

GO TO THE APPLICABLE DTC INSPECTION. 

1. Refer to DIAGNOSTIC TROUBLE CODE CHART

Result:  1

No 

See step  3

1. Start the engine and run it at idle speed.
2. Turn the A/C switch off.
3. Does the A/C compressor disengaged?

   Result

   Result
   Yes
   No

Result:  2

No 

PERFORM THE SYMPTOM TROUBLESHOOTING "NO. 24 A/C IS ALWAYS ON OR A/C COMPRESSOR RUNS CONTINUOUSLY". 

1. Refer to NO. 24 A/C IS ALWAYS ON OR A/C COMPRESSOR RUNS CONTINUOUSLY 

Result:  1

Yes 

See step  4

1. Access the Engine coolant temperature PID using the Techstream.

   Refer to ON-BOARD DIAGNOSTIC TEST

2. Compare the Engine coolant temperature PID and low engine coolant temperature indicator light and high engine coolant temperature warning light operation.
3. Is the Engine coolant temperature PID value same as indicator/warning light readings?

   Result

   Result
   Yes
   No

Result:  2

No 

INSPECT THE ECT SENSOR NO. 1. 

1. Refer to INSPECTION
2. If there is any malfunction:
   1. Replace the ECT sensor No. 1.

      Refer to REMOVAL

3. If there is no malfunction:
   1. Perform the combination meter symptom troubleshooting "LOW ENGINE COOLANT TEMPERATURE INDICATOR LIGHT/HIGH ENGINE COOLANT TEMPERATURE WARNING LIGHT ILLUMINATES OR FLASHES CONTINUOUSLY".

      Refer to LOW ENGINE COOLANT TEMPERATURE INDICATOR LIGHT/HIGH ENGINE COOLANT TEMPERATURE WARNING LIGHT ILLUMINATES OR FLASHES CONTINUOUSLY

Result:  1

Yes 

See step  5

1. Perform the Cooling Fan Control System Inspection.

   Refer to ON-VEHICLE INSPECTION

2. Does the cooling fan control system operate properly?

   Result

   Result
   Yes
   No

Result:  2

No 

REPAIR OR REPLACE THE MALFUNCTIONING PART ACCORDING TO THE INSPECTION RESULTS. 

Result:  1

Yes 

See step  6

1. Inspect the cooling system cap.

   Refer to INSPECTION

2. Is there any malfunction?

   Result

   Result
   Yes
   No

Result:  2

Yes 

REPLACE THE COOLING SYSTEM CAP. 

Result:  1

No 

See step  7

1. Inspect the following:
   1. Engine coolant level
   2. Engine coolant performance
   3. Water and anti-freeze mixture
   4. Thermostat (not fully open)
   5. Radiator (clogging)
   6. Fuses
2. Is there any malfunction?

   Result

   Result
   Yes
   No

Result:  2

Yes 

SERVICE IF NECESSARY. 

1. Repeat this step.

Result:  1

No 

See step  8

1. Inspect the engine coolant level.

   Refer to INSPECTION

2. Is there any malfunction?

   Result

   Result
   Yes
   No

Result:  2

Yes 

ADD ENGINE COOLANT AND VERIFY THAT THERE IS NO ENGINE COOLANT LEAKAGE. 

1. Refer to REPLACEMENT
2. Refer to INSPECTION
3. If there is any malfunction:
   1. Repair or replace the malfunctioning part according to the inspection results.

Result:  1

No 

See step  9

1. Verify the radiator hose tension.
   WARNING:

   • To prevent burns, use a cloth with your hand to verify the tension of the radiator hose.
2. After the engine warms up, does the engine coolant circulate to the radiator hose?

   Result

   Result
   Yes
   No

Result:  2

Yes 

See step  11

Result:  1

No 

See step  10

1. Inspect the thermostat.

   Refer to INSPECTION

2. Is the thermostat normal?

   Result

   Result
   Yes
   No

Result:  1

No 

REPLACE THE THERMOSTAT. 

1. Refer to REMOVAL

Result:  2

Yes 

INSPECT THE WATER PUMP. 

1. If there is any malfunction:
   1. Repair or replace the malfunctioning part according to the inspection results.

      Refer to REMOVAL

1. Inspect the drive belt.

   Refer to INSPECTION

2. Is the indicator mark on the drive belt auto tensioner within the normal range?

   Result

   Result
   Yes
   No

Result:  2

No 

REPLACE THE DRIVE BELT. 

1. Refer to REMOVAL

Result:  1

Yes 

See step  12

1. Inspect for clogging in the radiator.
2. Is there any malfunction?

   Result

   Result
   Yes
   No

Result:  1

No 

REPLACE THE ENGINE COOLANT. 

1. Refer to REPLACEMENT

Result:  2

Yes 

REPAIR OR REPLACE THE MALFUNCTIONING PART ACCORDING TO THE INSPECTION RESULTS.