On-Vehicle Inspection [09/2023 - ]: Procedure

WARNING: This page is about a different car, the 2024 Lexus TX 500h. However, it is still accessible from the selected car via links, so may be relevant.

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.
  1. For maintenance-free batteries:
    - If the electrolyte level is below the lower line, replace the battery.
  2. For non-maintenance-free batteries:
    - If the electrolyte level is below the lower line, add distilled water to each cell. Then, recharge the auxiliary 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 ignition switch off and turn on the 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.

Standard Voltage

Tester Connection	Condition	Specified Condition
Positive (+) auxiliary battery terminal - Negative (-) auxiliary battery terminal	20°C (68°F) Ignition switch off	12.0 V or higher

If the result is not as specified, recharge the 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 ignition switch off and turn on the headlights for 30 seconds. This will remove the surface charge from the auxiliary battery.
Turn the headlights off.

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

Standard Voltage

Tester Connection	Condition	Specified Condition
Positive (+) auxiliary battery terminal - Negative (-) auxiliary battery terminal	20°C (68°F), Ignition switch off	12.0 V or higher

If the result is not as specified, recharge or replace the auxiliary battery.

CHECK AUXILIARY BATTERY TERMINAL, FUSIBLE LINK AND FUSE

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

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

Standard

Battery Terminal	Specified Condition
Positive (+) terminal	5.0 Nm 51 kgfcm 44 in.*lbf
Negative (-) terminal	5.4 Nm 55 kgfcm 48 in.*lbf

NOTE:

After installing the battery state sensor assembly, make sure that the top of the negative (-) auxiliary battery terminal is above the top of the terminal clamp (on the same plane is also acceptable).

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

*1	Auxiliary Battery Terminal
*2	Terminal Clamp

Check whether the battery state sensor assembly is deformed or cracked.
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:

Orange wire harnesses and connectors indicate high-voltage circuits. To prevent electric shock, always follow the procedure described in the service information.

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Refer to PRECAUTION [09/2023 - ]

To prevent electric shock, wear insulated gloves when working on wire harnesses and components of the high voltage system.

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Remove the service plug grip.
NOTE:
After removing the service plug grip, turning the ignition switch to ON (READY) may cause a malfunction. Do not turn the ignition switch to ON (READY) unless instructed by the service information.
Confirm zero voltage.
HINT:

Refer to PRECAUTION [09/2023 - ]

Check that the AMD terminal is connected securely, and there is no contact problem.

*1	AMD Terminal (EV converter assembly Side)
*2	AMD Terminal (No. 1 Engine Room Relay Block and No. 1 Junction Block Assembly Side)

If there are any arc marks, replace the affected parts.

Check that the nut for the AMD terminal is tightened to the specified torque.
EV converter assembly side

Torque: 13.5 N*m (138 kgf*cm, 10 ft.*lbf)

No. 1 engine room relay block and No. 1 junction block assembly side

Torque: 8.0 N*m (82 kgf*cm, 71 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.

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 ignition 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	Ignition 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 DC/DC converter.