On-Vehicle Inspection [06/2018 - ]: Procedure

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INSPECT FOR COOLANT LEAK

WARNING:

Do not remove the radiator cap sub-assembly while the engine and radiator assembly are still hot. Pressurized, hot engine coolant and steam may be released and cause serious burns.

Remove the radiator cap sub-assembly.

Fill the radiator assembly with engine coolant, and then install a radiator cap tester.

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*a	Radiator Cap Tester

Warm up the engine.
Pump the radiator cap tester to 122 kPa (1.2 kgf/cm² , 18 psi), and then check that the pressure does not drop.
- 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 radiator cap sub-assembly.

INSPECT ENGINE COOLANT LEVEL IN RESERVOIR TANK

Check that the engine coolant level is between the L line and F line when the engine is cold.

*a	F Line
*b	L Line

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

NOTE:

Do not substitute plain water for engine coolant.

INSPECT ENGINE COOLANT QUALITY
WARNING:
Do not remove the radiator cap sub-assembly while the engine and radiator assembly are still hot. Pressurized, hot engine coolant and steam may be released and cause serious burns.
1. Remove the radiator cap sub-assembly.
2. Check if there are any excessive deposits of rust or scale around the radiator cap sub-assembly and water filler hole. Also, the engine coolant should be free of oil.
  If excessively dirty, replace the engine coolant.
3. Install the radiator cap sub-assembly.