On-Vehicle Inspection [09/2014 - 11/2017]: Procedure

WARNING: This page is about a different car, the 2017 Lexus RC 350, 2017 Lexus RC 300, 2016 Lexus RC 350, 2016 Lexus RC 300, and 2015 Lexus RC 350. However, it is still accessible from the selected car via links, so may be relevant.

INSPECT FOR COOLANT LEAK

Remove the radiator cap sub-assembly.

Fill the radiator reserve tank 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 118 kPa (1.2 kgf/cm² , 17 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

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.

NOTE:

Do not substitute plain water for engine coolant.

*a	Full Line
*b	Low Line

INSPECT ENGINE COOLANT QUALITY
1. Remove the radiator cap sub-assembly.
2. Check that there are no 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, clean the engine coolant passage and replace the engine coolant.
3. Install the radiator cap sub-assembly.