Caution / Notice / Hint

WARNING: This page is about a different car, the 2024 Lexus TX 550h+ and 2024 Lexus TX 500h. However, it is still accessible from the selected car via links, so may be relevant.

The necessary procedures (adjustment, calibration, initialization or registration) that must be performed after parts are removed and installed, or replaced during battery ECU assembly removal/installation are shown below.

NECESSARY PROCEDURES AFTER PARTS REMOVED/INSTALLED/REPLACED

Replaced Part or Performed Procedure	Necessary Procedure	Effect/Inoperative Function when Necessary Procedure not Performed	Link
Auxiliary battery terminal is disconnected/reconnected	Operate the multiplex network master switch assembly (retractable outer mirror switch) to extend and retract the outer rear view mirror assembly	Parking Support Brake System*	Refer to INITIALIZATION [09/2023 - ]
Replacement of battery ECU assembly	Current sensor offset learning	DTCs are stored	Refer to PROCEDURE - Step 10
	HV/EV battery thermal keep control mode setting*2	HV battery may become excessively weak Engine may not be able to be started	Refer to UTILITY [09/2023 - ]
	If possible, save the ECU Data from the previous Battery ECU assembly: ECU data save ECU data write	-
	If impossible, save the ECU Data from the previous Battery ECU assembly: Hybrid/EV battery pack serial number setting	-

*: When "[Parking Support Brake System icon] System Stopped See Owner's Manual" is displayed on the multi-information display.

WARNING:

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

NOTE:

After the ignition switch is turned off, there may be a waiting time before disconnecting the negative (-) auxiliary battery terminal.
Refer to BEFORE DISCONNECTING BATTERY [09/2023 - ]
To prevent the key from being locked in the vehicle, make sure to enter e-latch inspection mode and enable the manual release handle before disconnecting the cable from the negative (-) auxiliary battery terminal.
Refer to INSPECTION MODE PROCEDURE [09/2023 - ]
If the wrong type of battery ECU assembly is installed, the ignition switch cannot be turned on (READY).
After installing the battery ECU assembly, perform the following to check that the ignition switch can be turned on (READY).
- Turn the ignition switch to ON (READY).
- Turn the ignition switch off and wait for 30 seconds or more.
- Turn the ignition switch to ON (READY) again.

HINT:

When the cable is disconnected / reconnected to the auxiliary battery terminal, systems temporarily stop operating. However, each system has a function that completes learning the first time the system is used.

LEARNING COMPLETES WHEN VEHICLE IS DRIVEN

Effect/Inoperative Function when Necessary Procedure not Performed	Necessary Procedure	Link
Front Camera System	Drive the vehicle straight ahead at 35 km/h (22 mph) or more for 5 seconds or more.	Refer to INITIALIZATION [09/2023 - ]
Adaptive High Beam System
Lighting System (w/ Automatic Headlight Beam Level Control System)

LEARNING COMPLETES WHEN VEHICLE IS OPERATED NORMALLY

Effect/Inoperative Function when Necessary Procedure not Performed	Necessary Procedure	Link
Power Back Door System	Reset back door close position	Refer to INITIALIZATION [09/2023 - ]
Air Conditioning System	After the ignition switch is turned to ON, the servo motor and cooler expansion valve standard position is recognized.	-

COMPONENTS (REMOVAL)

Fig 1: Battery ECU (For PHEV Model) Removal Components

Procedure		Part Name Code
1	WHEN REPLACING BATTERY ECU ASSEMBLY	-	See step 1	-	-
2	HV SUPPLY BATTERY ASSEMBLY	G9510	-	-	-
3	NO. 1 TRACTION BATTERY COVER	-	See step 3	-	-
4	NO. 1 TRACTION BATTERY HEATER RELAY	G96J1	See step 4	-	-
5	NO. 3 TRACTION BATTERY WIRE COVER	G96E8	See step 5	-	-
6	BATTERY ECU ASSEMBLY	89890A	See step 6	-	-

*1	NO. 1 HV BATTERY SEAL	-	-
•	Non-reusable part	-	-