On-Vehicle Inspection [08/2023 - ]: Procedure

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CHECK RADIATOR CAP SUB-ASSEMBLY

WARNING:

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

Measure the valve opening pressure.

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

*a	Rubber Packing (1)
*b	Rubber Packing (2)
*c	Rubber Packing (3)
*d	Valve Seat

If there are water stains or foreign matter on the rubber packing (1), (2) or (3), clean the part(s) with water and finger scouring.
Check that the rubber packings (1), (2) and (3) are not deformed, cracked or swollen.
Check that the rubber packing (3) and valve seat are not stuck together.
Apply engine coolant to the rubber packings (2) and (3) before using a radiator cap tester.

When using the radiator cap tester, tilt it upward 30° or more.

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

*1	Radiator Cap Sub-assembly
*a	Radiator Cap Tester
*b	30° or more

Pump the radiator cap tester several times, and check the maximum pressure.

Pumping Speed

1 pump per second

Result

Item	Specified Condition	Result
Standard pressure (for brand-new radiator cap sub-assembly)	74 to 103 kPa 0.8 to 1.1 kgf/cm² 10.7 to 14.9 psi	kPa kgf/cm₂ psi
Minimum pressure (for used radiator cap sub-assembly)	59 kPa 0.6 kgf/cm² 8.6 psi	kPa kgf/cm₂ psi

HINT:

Even if the radiator cap sub-assembly cannot maintain the maximum pressure, it is not a defect.

If the maximum pressure is less than the minimum pressure, replace the radiator cap sub-assembly.

CHECK RADIATOR ASSEMBLY FOR CLOGGING

WARNING:

To prevent burns, do not touch the engine or other high temperature components while the engine is hot.

Pre-procedure1

Remove the radiator cool air intake duct seal.
Remove the inlet air cleaner assembly.

Shine an electric light at the radiator assembly from the front and check the radiator assembly for clogging using a mirror.

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

*a	OK	*b	NG
*c	Electric Light	*d	Mirror
*e	Areas to be checked	-	-

The radiator assembly is not clogged.

If the radiator assembly is clogged, clean it.

Post-procedure1

Install the inlet air cleaner assembly.
Install the radiator cool air intake duct seal.

CLEAN COOLER CONDENSER ASSEMBLY

WARNING:

To prevent burns, do not touch the engine or other high temperature components while the engine is hot.

Pre-procedure1

Remove the radiator cool air intake duct seal.
Remove the inlet air cleaner assembly.
Cover the opening of each air duct with a piece of cloth.

Check that the washer nozzle is not clogged.

Insert the washer nozzle into the space in front and spray it.

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

NOTE:

Clean the fins of the cooler condenser assembly and radiator assembly (for Inverter Coolant) by spraying the entire area for 150 seconds. Repeat this process twice.
Set the air pressure to 0.4 MPa (4.1 kgf/cm² , 58 psi).
Check that water sprays in mist form from the washer nozzle.
Keep the washer nozzle parallel to the cooler condenser assembly and radiator assembly (for Inverter Coolant).
Do not allow the washer nozzle to contact the fins of the cooler condenser assembly and radiator assembly (for Inverter Coolant).
Keep the washer nozzle moving while spraying water.
Do not spray the cooler compressor assembly excessively.

Leave the cooler condenser assembly and radiator assembly (for Inverter Coolant) as is for 10 minutes to let the water penetrate the dirt.
Clean the cooler condenser assembly and radiator assembly (for Inverter Coolant) again.
NOTE:
- Clean the fins of the cooler condenser assembly and radiator assembly (for Inverter Coolant) by spraying the entire area for 150 seconds. Repeat this process 4 times.
- Set the air pressure to 0.4 MPa (4.1 kgf/cm² , 58 psi).
- Check that water sprays in mist form from the washer nozzle.
- Keep the washer nozzle parallel to the cooler condenser assembly and radiator assembly (for Inverter Coolant).
- Do not allow the washer nozzle to contact the fins of the cooler condenser assembly and radiator assembly (for Inverter Coolant).
- Keep the washer nozzle moving while spraying water.
- Do not spray the cooler compressor assembly excessively.
Using an air blow gun, dry the cooler condenser assembly and radiator assembly (for Inverter Coolant) for 3 minutes.

Post-procedure1

Install the inlet air cleaner assembly.
Install the radiator cool air intake duct seal.

CLEAN RADIATOR ASSEMBLY

WARNING:

To prevent burns, do not touch the engine or other high temperature components while the engine is hot.

Pre-procedure1

Remove the radiator cool air intake duct seal.
Remove the inlet air cleaner assembly.
Cover the opening of each air duct with a piece of cloth.

Disconnect the cooling fan motor connector.

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Disengage the 2 clamps to disconnect the wire harness from the fan with motor assembly.

Rotate the lever while pushing the lock, and disconnect the cooling fan motor connector.

NOTE:

After disconnecting the cooling fan motor connector, make sure that dirt, water or other foreign matter does not contact the connecting parts of the cooling fan motor connector.

Disengage the 2 clamps to disconnect the wire harness from the fan with motor assembly.

Disengage the 2 claws and separate the fan with motor assembly from the radiator assembly.

Insert the washer nozzle between the radiator assembly and fan with motor assembly and spray the radiator assembly.

NOTE:

Clean the fins of the radiator assembly by spraying the entire area for 150 seconds. Repeat this process twice.
Set the air pressure to 0.4 MPa (4.1 kgf/cm² , 58 psi).
Check that water sprays in mist form from the washer nozzle.
Keep the washer nozzle parallel to the radiator assembly.
Do not allow the washer nozzle to contact the fins of the radiator assembly.
Keep the washer nozzle moving while spraying water.

Leave the radiator assembly as is for 10 minutes to let the water penetrate the dirt.
Clean the radiator assembly again.
NOTE:
- Clean the fins of the radiator assembly by spraying the entire area for 150 seconds. Repeat this process 4 times.
- Set the air pressure to 0.4 MPa (4.1 kgf/cm² , 58 psi).
- Check that water sprays in mist form from the washer nozzle.
- Keep the washer nozzle parallel to the radiator assembly.
- Do not allow the washer nozzle to contact the fins of the radiator assembly.
- Keep the washer nozzle moving while spraying water.
Using an air blow gun, dry the radiator assembly for 3 minutes.

Post-procedure1

Check the fins of the radiator assembly for clogs again.
If the radiator assembly is clogged, clean the radiator assembly, cooler condenser assembly and radiator assembly (for Inverter Coolant) again.

Check that the 2 guides at the bottom are engaged to the radiator assembly.

Engage the 2 claws to install the fan with motor assembly to the radiator assembly.

Engage the 2 clamps to connect the wire harness to the fan with motor assembly.

Connect the cooling fan motor connector and rotate the lever to lock it.
NOTE:
- When connecting the cooling fan motor connector, make sure that the connecting parts of the cooling fan motor connector are free of dirt, water or other foreign matter.
- Be sure to securely connect the cooling fan motor connector.
Engage the 2 clamps to connect the wire harness to the fan with motor assembly.
Connect the cooling fan motor connector.
Remove the piece of cloth from the opening of each air duct.
Install the inlet air cleaner assembly.
Install the radiator cool air intake duct seal.