On-Vehicle Inspection [08/2015 - ]: Procedure

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INSPECT FOR COOLANT LEAK

Remove the reserve tank cap.
Fill the radiator reserve tank assembly with engine coolant, and then install a radiator cap tester.
Warm up the engine.

Pump the radiator cap tester to 137 kPa (1.4 kgf/cm² , 20 psi), and then check that the pressure does not drop.

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*a	Radiator Cap Tester

If the pressure drops, check the hoses, radiator assembly and engine water pump assembly for leaks.
If there are no signs of external engine coolant leaks, check the heater core, cylinder block sub-assembly and cylinder head sub-assembly.

Remove the radiator cap tester.
Install the reserve tank cap.

INSPECT ENGINE COOLANT LEVEL IN RESERVOIR

Check that the engine coolant level is between the low line and full line when the engine is cold.

If the engine coolant level is low, check for leaks and add engine coolant to the full line.

*a	Full Line
*b	Low Line

NOTE:

Do not substitute plain water for engine coolant.

INSPECT ENGINE COOLANT QUALITY
1. Remove the reserve tank cap.
2. Check that there are no excessive deposits of rust or scale around the reserve tank cap and radiator reserve tank filler hole. Also, the engine coolant should be free of oil.
  If excessively dirty, replace the engine coolant.
3. Install the reserve tank cap.