On-Vehicle Inspection [10/2018 - ]: Procedure

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CHECK AUXILIARY BATTERY
1. Check that the auxiliary battery cables are connected to the correct terminals.
  If they are not, connect them properly.
2. Check the auxiliary battery for damage and deformation. If severe damage, deformation or leakage is found, replace the auxiliary battery.
3. Check the electrolyte level in each cell.
  - If the electrolyte level is below the lower line, replace the auxiliary battery.
  - If the electrolyte level is below the lower line, add distilled water to each cell. Then, recharge the battery and check the electrolyte specific gravity.
    Standard Specific Gravity
    
    1.25 or higher at 20°C (68°F)

CHECK AUXILIARY BATTERY VOLTAGE

Turn the power switch off and turn on the high beam headlights for 30 seconds. This will remove the surface charge from the auxiliary battery.

Measure the auxiliary battery voltage according to the value(s) in the table below.

Result

Tester Connection	Condition	Specified Condition	Result
Positive (+) auxiliary battery terminal - Negative (-) auxiliary battery terminal	20°C (68°F), Power switch off	12.0 V or higher	Auxiliary battery is OK
	20°C (68°F), Power switch off	12.0 V or less	Recharge auxiliary battery

RECHARGE AUXILIARY BATTERY

Recharge the auxiliary battery.

HINT:

Recharge the auxiliary battery according to the charger's instructions.
Apply the appropriate charging current according to the type of auxiliary battery shown in the table below.

Charge Method	Charging Current
Normal	Below 5 A
Quick	Below 15 A

Turn the power switch off and turn on the high beam headlights for 30 seconds. This will remove the surface charge from the auxiliary battery.

Measure the auxiliary battery voltage according to the value(s) in the table below.

Result

Tester Connection	Condition	Specified Condition	Result
Positive (+) auxiliary battery terminal - Negative (-) auxiliary battery terminal	20°C (68°F), Power switch off	12.0 V or higher	Auxiliary battery is OK
	20°C (68°F), Power switch off	12.0 V or less	Recharge auxiliary battery

CHECK AUXILIARY BATTERY TERMINAL, FUSIBLE LINK AND FUSE

Check that the auxiliary battery terminals are not loose or corroded.

Positive (+) Auxiliary Battery Terminal

Torque: 5.4 N.m (55 kgf/cm, 48 in.lbf)

Negative (-) Auxiliary Battery Terminal

Torque: 5.4 N.m (55 kgf/cm, 48 in.lbf)

If a terminal is loose or corroded, tighten or clean the terminal.

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

*a	Positive (+) Auxiliary Battery Terminal
*b	Negative (-) Auxiliary Battery Terminal

Measure the resistance of each fusible link and fuse for the auxiliary battery charging system.
Standard Resistance

Below 1 Ω

If the result is not as specified, replace the fusible link or fuse as necessary.

CHECK AMD TERMINAL

WARNING:

This vehicle has contains high voltage circuits standardized with orange colored wiring and connectors, so follow the instructions in this service information to perform the procedures correctly.

Refer to PRECAUTION [10/2018 - 07/2022] , or refer to PRECAUTION [07/2022 - ]

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

If the correct procedures are not followed according to the instructions in this service information, there is a danger of electric shock from the high voltage circuits.

Be sure to wear insulating gloves when working on high voltage wiring or components.

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

If work is performed without wearing insulating gloves, there is a danger of electric shock.

Remove the service plug grip.
Refer to REMOVAL [10/2018 - 07/2022] , or refer to REMOVAL [07/2022 - ]
Check that the AMD terminal is connected securely, and there is no contact problem.
If there are any arc marks, replace the affected parts.

Check that the nut for the AMD terminal is tightened to the specified torque.

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

*a	Inverter with Converter Assembly Side
*b	No. 1 Engine Room Relay Block Side

Inverter with Converter Assembly Side

Torque: 8.0 N.m (82 kgf/cm, 71 in.lbf)

No. 1 Engine Room Relay Block Side

Torque: 8.4 N.m (86 kgf/cm, 74 in.lbf)

If there are no arc marks and the AMD terminal connection is faulty, connect the AMD terminal securely.

Install the service plug grip.
Refer to INSTALLATION [10/2018 - ]

CHECK DC/DC CONVERTER FUNCTION

Connect the AC/DC 400 A probe to the positive (+) auxiliary battery cable.

*a	Probe Direction
*b	Current Flowing into Auxiliary Battery

Turn the power switch on (READY) and leave the vehicle as is until the electric current flowing to the auxiliary battery becomes 10 A or less.
Turn on the high beam headlights, and turn the blower motor switch to the HI position and the rear window defogger on.

Measure the current and voltage according to the value(s) in the table below.

*a	Probe Direction
*b	Current Flowing from Auxiliary Battery

Result

Item	Tester Connection	Condition	Specified Condition
Current flowing from auxiliary battery	Positive (+) auxiliary battery cable	Power switch on (READY) (The high beam headlights are on, the blower motor switch is in the HI position, and the rear window defogger is turned on.)	0 A or less (No current from auxiliary battery)
Auxiliary battery voltage	Positive (+) auxiliary battery terminal - Negative (-) auxiliary battery terminal		12.5 to 15 V

If the result is not as specified, replace the inverter with converter assembly.