On-Vehicle Inspection [10/2022 - ]: Procedure

WARNING: This page is about a different car, the 2025 Lexus RX 350, 2024 Lexus RX 350, and 2023 Lexus RX 350. However, it is still accessible from the selected car via links, so may be relevant.

CHECK BATTERY CONDITION

NOTE:

If the battery is weak or if the engine is difficult to start, recharge the battery and perform inspections again before returning the vehicle to the customer.

Check the battery for damage or deformation. If severe damage, deformation or leakage is found, replace the battery.
Check the voltage.
1. For maintenance-free batteries:
  - If the electrolyte level is below the lower line, replace the battery.
  - If the electrolyte level is above the lower line, check the battery voltage when cranking the engine. If the voltage is less than 11 V, recharge or replace the battery.
    HINT:
    
    Before checking the battery voltage, turn off all the electrical systems (headlights, blower motor, rear window defogger, etc.).
2. For non-maintenance-free batteries:
  - 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)
  - If the electrolyte level is above the lower line, check the battery voltage when cranking the engine. If the battery voltage is less than 11 V, recharge or replace the battery.
    HINT:
    
    Before checking the battery voltage, turn off all the electrical systems (headlights, blower motor, rear window defogger, etc.).

Check the voltage.

Turn the ignition switch off and turn on the headlights for 20 to 30 seconds. This will remove the surface charge from the battery.

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

Standard Voltage

Tester Connection	Condition	Specified Condition	Result
Positive (+) terminal - Negative (-) terminal	20°C (68°F)	12.3 V or higher	V

HINT:

20°C = 68°F

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

CHECK BATTERY TERMINAL

Check that the battery terminals are not loose or corroded.

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

Standard

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

CHECK FUSES

Measure the resistance of each fuse for the charging system.

HINT:

The fuses shown in System Diagram are related to the charging system.

Standard Resistance

Specified Condition	Result
Below 1 Ω	Ω

If the result is not as specified, replace the fuse.

INSPECT FAN AND GENERATOR V BELT
Refer to PROCEDURE - Step 7
INSPECT GENERATOR ASSEMBLY WIRING
1. Visually check the generator assembly wiring.
  1. Check that the wiring is in good condition.
CHECK FOR ABNORMAL NOISE
1. Check for abnormal noises from the generator assembly.
  1. Check that no abnormal noises are heard from the generator assembly while the engine is running.
    If noise occurs, refer to Problem Symptoms Table.
    
    HINT:
    
    Refer to PROBLEM SYMPTOMS TABLE [10/2022 - ]

INSPECT CHARGING CIRCUIT WITHOUT LOAD

WARNING:

To prevent injury due to contact with an operating V-ribbed belt or cooling fan, keep your hands and clothing away from the V-ribbed belt and cooling fans when working in the engine compartment with the engine running or the ignition switch ON.
To prevent burns, do not touch the engine, exhaust manifold or other high temperature components while the engine is hot.

Pre-procedure1

Connect a voltmeter and an ammeter to the charging circuit as follows.

HINT:

If a battery/generator assembly tester is available, connect the tester to the charging circuit in accordance with the manufacturer's instructions.

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

*1	Generator Assembly
*2	Battery
*a	Terminal B

Disconnect the wire from terminal B of the generator assembly and connect it to the negative (-) lead of the ammeter.
Connect the ammeter positive (+) lead to terminal B of the generator assembly.
Connect the voltmeter positive (+) lead to the positive (+) terminal of the battery.
Ground the voltmeter negative (-) lead.

Check the charging circuit.

Maintain the engine speed at 2000 rpm and check the readings on the ammeter and voltmeter.

Standard Current

Specified Condition	Result
10 A or higher	A

Standard Voltage

Specified Condition	Result
12.7 to 15.3 V	V

If the result is not as specified, repair or replace the generator assembly.

Post-procedure1

None.

INSPECT CHARGING CIRCUIT WITH LOAD

WARNING:

To prevent injury due to contact with an operating V-ribbed belt or cooling fan, keep your hands and clothing away from the V-ribbed belt and cooling fans when working in the engine compartment with the engine running or the ignition switch ON.
To prevent burns, do not touch the engine, exhaust manifold or other high temperature components while the engine is hot.

Pre-procedure1

With the engine running at 2000 rpm, turn the high beam headlights on and turn the heater blower switch to the "HI" position.

Check the reading on the ammeter.

Standard Current

Specified Condition	Result
30 A or higher	A

If the result is not as specified, repair or replace the generator assembly.

HINT:

If the battery is fully charged, the reading will sometimes be less than the standard current. In this case, add more electrical load (operate the wipers, rear window defogger, etc.) and check the reading on the ammeter again.

Post-procedure1

None.