Last Modified: 07-31-2024 6.11:8.1.0 Doc ID: RM100000001N369
Model Year Start: 2021 Model: Corolla Prod Date Range: [04/2020 - 09/2022]
Title: HYBRID / BATTERY CONTROL: BATTERY ECU (for LITHIUM-ION BATTERY): REMOVAL; 2021 - 2022 MY Corolla Corolla HV [04/2020 - 09/2022]

REMOVAL

CAUTION / NOTICE / HINT

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

Perform steering sensor zero point calibration

Lane Control System

2020 - 2022 MY Corolla Corolla HV [01/2019 - 09/2022]; PRE-COLLISION: PRE-COLLISION SYSTEM (for HV Model): INITIALIZATION

Pre-collision System

Replacement of battery ECU assembly

Current sensor offset learning

DTCs are stored

2021 - 2022 MY Corolla Corolla HV [04/2020 - 09/2022]; HYBRID / BATTERY CONTROL: HV RELAY ASSEMBLY (for LITHIUM-ION BATTERY): INSTALLATION+

CAUTION:

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

    Click here 2021 - 2022 MY Corolla Corolla HV [04/2020 - 09/2022]; HYBRID / BATTERY CONTROL: HYBRID CONTROL SYSTEM (for LITHIUM-ION BATTERY with P610): PRECAUTION

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

NOTICE:

  • After the power switch is turned off, the radio and display receiver assembly records various types of memory and settings. As a result, after turning the power switch off, make sure to wait at least 85 seconds before disconnecting the cable from the negative (-) auxiliary battery terminal. (for Audio and Visual System (for HV Model))
  • The type of battery ECU assembly to be used varies depending on the vehicle model.
  • The type of battery ECU assembly can be confirmed by the color of the label.

    *a

    Black Label

  • If the wrong type of battery ECU assembly is installed, the power switch cannot be turned on (READY).
  • After installing the battery ECU assembly, perform the following to check that the power switch can be turned on (READY).
    • Turn the power switch on (READY).
    • Turn the power switch off and wait for 30 seconds or more.
    • Turn the power switch on (READY) again.

PROCEDURE

1. PRECAUTION

Click here 2019 - 2025 MY Corolla Corolla Hatchback Corolla HV GR Corolla [06/2018 -        ]; INTRODUCTION: REPAIR INSTRUCTION: PRECAUTION

2. WHEN REPLACING BATTERY ECU ASSEMBLY

HV battery learning values are stored in the battery ECU assembly and ECM and are used to detect malfunctions and illuminate the hybrid battery indicator light in the combination meter assembly. When either of these ECUs is replaced, the new ECU receives the HV battery learning values from the other ECU and stores them.

NOTICE:

  • Do not replace the battery ECU assembly and ECM at the same time as the HV battery learning values will be lost. However, if it is necessary to replace both ECUs at the same time, replace them by following the procedure below.
  • Do not replace the battery ECU assembly or ECM with a used one from another vehicle.

(a) Procedure when replacing both battery ECU assembly and ECM:

(1) Disconnect the cable from the negative (-) auxiliary battery terminal.

(2) Replace either ECU.

(3) Connect the cable to the negative (-) auxiliary battery terminal.

(4) Turn the power switch on (READY) and wait for 5 minutes or more.

(5) Turn the power switch off and disconnect the cable from the negative (-) auxiliary battery terminal.

(6) Replace the other ECU.

(7) Connect the cable to the negative (-) auxiliary battery terminal.

(8) Check that the power switch can be turned on (READY).

HINT:

If the battery ECU assembly and ECM are replaced at the same time without following the above procedure, replace either of the ECUs with its original one and then replace it again by following the above procedure. If the correct procedure is not followed, perform the procedure again from the beginning.

3. REMOVE SERVICE PLUG GRIP

Click here 2021 - 2022 MY Corolla Corolla HV [04/2020 - 09/2022]; HYBRID / BATTERY CONTROL: SERVICE PLUG GRIP: REMOVAL

4. DISCONNECT ENGINE WIRE

Click here 2021 - 2022 MY Corolla Corolla HV [04/2020 - 09/2022]; HYBRID / BATTERY CONTROL: FRAME WIRE: REMOVAL+

5. REMOVE CONNECTOR COVER ASSEMBLY

Click here 2021 - 2022 MY Corolla Corolla HV [04/2020 - 09/2022]; HYBRID / BATTERY CONTROL: INVERTER WITH CONVERTER: REMOVAL+

6. CHECK TERMINAL VOLTAGE

Click here 2021 - 2022 MY Corolla Corolla HV [04/2020 - 09/2022]; HYBRID / BATTERY CONTROL: INVERTER WITH CONVERTER: REMOVAL+

7. INSTALL CONNECTOR COVER ASSEMBLY

Click here 2021 - 2022 MY Corolla Corolla HV [04/2020 - 09/2022]; HYBRID / BATTERY CONTROL: HV BATTERY (for LITHIUM-ION BATTERY): REMOVAL+

8. CONNECT ENGINE WIRE

Click here 2021 - 2022 MY Corolla Corolla HV [04/2020 - 09/2022]; HYBRID / BATTERY CONTROL: FRAME WIRE: INSTALLATION+

9. DISCONNECT REAR SEAT CENTER LAP TYPE BELT ASSEMBLY

Click here 2020 - 2025 MY Corolla Corolla Hatchback Corolla HV GR Corolla [01/2019 -        ]; SEAT: REAR SEAT ASSEMBLY: REMOVAL+

10. REMOVE REAR SEAT CUSHION ASSEMBLY

Click here 2020 - 2025 MY Corolla Corolla Hatchback Corolla HV GR Corolla [01/2019 -        ]; SEAT: REAR SEAT ASSEMBLY: REMOVAL+

11. REMOVE REAR SEAT CUSHION LOCK HOOK

Click here 2020 - 2025 MY Corolla Corolla Hatchback Corolla HV GR Corolla [01/2019 -        ]; SEAT: REAR SEAT ASSEMBLY: REMOVAL+

12. REMOVE REAR DOOR SCUFF PLATE LH

Click here 2021 - 2022 MY Corolla Corolla Hatchback Corolla HV GR Corolla [04/2020 - 09/2022]; INTERIOR PANELS / TRIM: ROOF HEADLINING (for Sedan): REMOVAL+

13. REMOVE REAR UNDER SIDE COVER LH

Click here 2021 - 2022 MY Corolla Corolla Hatchback Corolla HV GR Corolla [04/2020 - 09/2022]; INTERIOR PANELS / TRIM: ROOF HEADLINING (for Sedan): REMOVAL+

14. REMOVE REAR DOOR SCUFF PLATE RH

HINT:

Use the same procedure as for the LH side.

15. REMOVE REAR UNDER SIDE COVER RH

HINT:

Use the same procedure as for the LH side.

16. REMOVE REAR UNDER COVER

Click here 2020 - 2022 MY Corolla Corolla HV [01/2019 - 09/2022]; HYBRID / BATTERY CONTROL: HV BATTERY (for NICKEL METAL HYDRIDE BATTERY): REMOVAL+

17. REMOVE REAR SEAT CUSHION LEG SUB-ASSEMBLY

Click here 2021 - 2022 MY Corolla Corolla HV [04/2020 - 09/2022]; HYBRID / BATTERY CONTROL: HV BATTERY (for LITHIUM-ION BATTERY): REMOVAL+

18. REMOVE NO. 1 HV BATTERY COVER PANEL RH

Click here 2021 - 2022 MY Corolla Corolla HV [04/2020 - 09/2022]; HYBRID / BATTERY CONTROL: HV BATTERY (for LITHIUM-ION BATTERY): REMOVAL+

19. REMOVE HYBRID BATTERY HOSE ASSEMBLY

Click here 2021 - 2022 MY Corolla Corolla HV [04/2020 - 09/2022]; HYBRID / BATTERY CONTROL: HV BATTERY (for LITHIUM-ION BATTERY): REMOVAL+

20. DISCONNECT FLOOR WIRE

Click here 2021 - 2022 MY Corolla Corolla HV [04/2020 - 09/2022]; HYBRID / BATTERY CONTROL: HV BATTERY (for LITHIUM-ION BATTERY): REMOVAL+

21. REMOVE NO. 4 HV BATTERY PROTECTOR

Click here 2021 - 2022 MY Corolla Corolla HV [04/2020 - 09/2022]; HYBRID / BATTERY CONTROL: HV BATTERY (for LITHIUM-ION BATTERY): REMOVAL+

22. DISCONNECT FLOOR WIRE

Click here 2021 - 2022 MY Corolla Corolla HV [04/2020 - 09/2022]; HYBRID / BATTERY CONTROL: HV BATTERY (for LITHIUM-ION BATTERY): REMOVAL+

23. REMOVE UPPER NO. 1 HYBRID BATTERY COVER SUB-ASSEMBLY

CAUTION:

Be sure to wear insulated gloves and protective goggles.

(a) Remove the 6 bolts, 5 nuts and upper No. 1 hybrid battery cover sub-assembly from the HV battery.

24. REMOVE NO. 1 HV BATTERY HOSE

CAUTION:

Be sure to wear insulated gloves and protective goggles.

(a) Remove the clip and No. 1 HV battery hose from the HV battery.

25. REMOVE NO. 1 HYBRID BATTERY SHIELD SUB-ASSEMBLY

CAUTION:

Be sure to wear insulated gloves and protective goggles.

(a) Disengage the clamp.

(b) Remove the nut and No. 1 hybrid battery shield sub-assembly from the HV battery.

26. REMOVE NO. 1 HV BATTERY PROTECTOR

CAUTION:

Be sure to wear insulated gloves and protective goggles.

(a) Disengage the clamp to disconnect the wire harness.

(b) Remove the 3 nuts.

(c) Disengage the 2 claws and remove the No. 1 HV battery protector from the No. 2 HV battery protector.

27. REMOVE BATTERY ECU ASSEMBLY

CAUTION:

Be sure to wear insulated gloves and protective goggles.

(a) Disconnect the 6 battery ECU assembly connectors.

NOTICE:

Insulate each disconnected high-voltage connector with insulating tape. Wrap the connector from the wire harness side to the end of the connector.

(b) Remove the 3 nuts and battery ECU assembly from the HV battery.

NOTICE:

If the battery ECU assembly has been struck or dropped, replace it.

28. REMOVE NO. 2 HV BATTERY PROTECTOR

CAUTION:

Be sure to wear insulated gloves and protective goggles.

HINT:

Perform this procedure only when replacement of the No. 2 HV battery protector is necessary.

(a) Disconnect each wire harness from the No. 2 HV battery protector.

(b) Disengage the claw and remove the No. 2 HV battery protector from the HV battery.