Last Modified: 07-31-2024 6.11:8.1.0 Doc ID: RM100000001GCME
Model Year Start: 2020 Model: Corolla Prod Date Range: [01/2019 - 09/2022]
Title: HYBRID / BATTERY CONTROL: HYBRID CONTROL SYSTEM (for NICKEL METAL HYDRIDE BATTERY): PRECAUTION; 2020 - 2022 MY Corolla Corolla HV [01/2019 - 09/2022]

PRECAUTION

PRECAUTIONS FOR INSPECTING HYBRID CONTROL SYSTEM

(a) Before the following operations are conducted, take precautions to prevent electric shock by turning the power switch off, wearing insulated gloves, and removing the service plug grip from HV battery.

  • Inspecting the high-voltage system
  • Disconnecting the low voltage connector of the inverter with converter assembly
  • Disconnecting the low voltage connector of the HV battery

NOTICE:

  • After turning the power switch off, waiting time may be required before disconnecting the cable from the negative (-) auxiliary battery terminal. Therefore, make sure to read the disconnecting the cable from the negative (-) auxiliary battery terminal notices before proceeding with work.

    Click here 2020 MY Corolla Corolla Hatchback Corolla HV GR Corolla [01/2019 - 03/2019]; INTRODUCTION: REPAIR INSTRUCTION: INITIALIZATION 2020 MY Corolla Corolla Hatchback Corolla HV GR Corolla [03/2019 - 09/2019]; INTRODUCTION: REPAIR INSTRUCTION: INITIALIZATION 2020 MY Corolla Corolla Hatchback Corolla HV GR Corolla [09/2019 - 04/2020]; INTRODUCTION: REPAIR INSTRUCTION: INITIALIZATION 2021 - 2022 MY Corolla Corolla Hatchback Corolla HV GR Corolla [04/2020 - 09/2022]; INTRODUCTION: REPAIR INSTRUCTION: INITIALIZATION

  • After removing the service plug grip, turning the power switch on (READY) may cause a malfunction. Do not turn the power switch on (READY) unless instructed by the repair manual.

(b) To prevent electric shock, make sure to remove the service plug grip to cut off the high voltage circuit before servicing the vehicle.

(c) After removing the service plug grip, put it in your pocket to prevent other technicians from accidentally reconnecting it while you are working on the high-voltage system.

(d) After removing the service plug grip, wait for at least 10 minutes before touching any of the high-voltage connectors or terminals.

HINT:

Waiting for at least 10 minutes is required to discharge the high-voltage capacitor inside the inverter with converter assembly.

*a

Without waiting for 10 minutes

(e) Check the voltage at the terminals in the inspection point of the inverter with converter assembly.

CAUTION:

Be sure to wear insulated gloves.

(1) Remove the connector cover assembly from the inverter with converter assembly.

Click here 2020 MY Corolla Corolla HV [01/2019 - 04/2020]; HYBRID / BATTERY CONTROL: INVERTER WITH CONVERTER: REMOVAL+ 2021 - 2022 MY Corolla Corolla HV [04/2020 - 09/2022]; HYBRID / BATTERY CONTROL: INVERTER WITH CONVERTER: REMOVAL+

NOTICE:

  • Do not touch the connector cover assembly waterproof seal.
  • Do not allow any foreign matter or water to enter the inverter with converter assembly.

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

Standard Voltage:

Tester Connection

Condition

Specified Condition

Inspection point

At least 10 minutes after removing the service plug grip

0 V

HINT:

Set the tester to DC750 V or more to measure the voltage.

(3) Reinstall the connector cover assembly.

(f) When turning the power switch on (IG) during an inspection, do not press the power switch with the brake pedal depressed.

CAUTION:

Pressing the power switch with the brake pedal depressed causes the system to enter the READY-on state. This is very dangerous because high voltage may be applied to the inspection area.

(g) Turn the power switch off, wear insulated gloves, and disconnect the cable from the negative (-) terminal of the auxiliary battery before touching any of the orange-colored wires of the high-voltage system.

NOTICE:

After turning the power switch off, waiting time may be required before disconnecting the cable from the negative (-) auxiliary battery terminal. Therefore, make sure to read the disconnecting the cable from the negative (-) auxiliary battery terminal notices before proceeding with work.

Click here 2020 MY Corolla Corolla Hatchback Corolla HV GR Corolla [01/2019 - 03/2019]; INTRODUCTION: REPAIR INSTRUCTION: INITIALIZATION 2020 MY Corolla Corolla Hatchback Corolla HV GR Corolla [03/2019 - 09/2019]; INTRODUCTION: REPAIR INSTRUCTION: INITIALIZATION 2020 MY Corolla Corolla Hatchback Corolla HV GR Corolla [09/2019 - 04/2020]; INTRODUCTION: REPAIR INSTRUCTION: INITIALIZATION 2021 - 2022 MY Corolla Corolla Hatchback Corolla HV GR Corolla [04/2020 - 09/2022]; INTRODUCTION: REPAIR INSTRUCTION: INITIALIZATION

(h) Turn the power switch off before performing any resistance checks.

(i) Turn the power switch off before disconnecting or reconnecting any connectors.

(j) When performing work involving high-voltage wires, use either a tool wrapped with vinyl insulating tape or an insulated tool.

(k) When high-voltage connectors are removed, wrap the connectors with insulation tape to prevent them from contacting foreign matter.

NOTICE FOR HYBRID CONTROL SYSTEM ACTIVATION

(a) When the warning is illuminated, or the auxiliary battery has been disconnected and reconnected, attempting to turn the power switch on (READY) may not start the system (the system may not enter the READY-on state) on the first attempt. If so, turn the power switch off and reattempt to start the hybrid system.

NOTICE:

After turning the power switch off, waiting time may be required before disconnecting the cable from the negative (-) auxiliary battery terminal. Therefore, make sure to read the disconnecting the cable from the negative (-) auxiliary battery terminal notices before proceeding with work.

Click here 2020 MY Corolla Corolla Hatchback Corolla HV GR Corolla [01/2019 - 03/2019]; INTRODUCTION: REPAIR INSTRUCTION: INITIALIZATION 2020 MY Corolla Corolla Hatchback Corolla HV GR Corolla [03/2019 - 09/2019]; INTRODUCTION: REPAIR INSTRUCTION: INITIALIZATION 2020 MY Corolla Corolla Hatchback Corolla HV GR Corolla [09/2019 - 04/2020]; INTRODUCTION: REPAIR INSTRUCTION: INITIALIZATION 2021 - 2022 MY Corolla Corolla Hatchback Corolla HV GR Corolla [04/2020 - 09/2022]; INTRODUCTION: REPAIR INSTRUCTION: INITIALIZATION

PRECAUTIONS FOR DISCONNECTING AMD TERMINAL

HINT:

The AMD terminal is connected to the positive (+) terminal of the auxiliary battery. To prevent damage when disconnecting the AMD terminal, perform the following procedures.

(a) Be sure to disconnect the cable from the negative (-) auxiliary battery terminal before disconnecting the AMD terminal from the fusible link assembly.

NOTICE:

After turning the power switch off, waiting time may be required before disconnecting the cable from the negative (-) auxiliary battery terminal. Therefore, make sure to read the disconnecting the cable from the negative (-) auxiliary battery terminal notices before proceeding with work.

Click here 2020 MY Corolla Corolla Hatchback Corolla HV GR Corolla [01/2019 - 03/2019]; INTRODUCTION: REPAIR INSTRUCTION: INITIALIZATION 2020 MY Corolla Corolla Hatchback Corolla HV GR Corolla [03/2019 - 09/2019]; INTRODUCTION: REPAIR INSTRUCTION: INITIALIZATION 2020 MY Corolla Corolla Hatchback Corolla HV GR Corolla [09/2019 - 04/2020]; INTRODUCTION: REPAIR INSTRUCTION: INITIALIZATION 2021 - 2022 MY Corolla Corolla Hatchback Corolla HV GR Corolla [04/2020 - 09/2022]; INTRODUCTION: REPAIR INSTRUCTION: INITIALIZATION

*1

AMD Terminal (Inverter with Converter Assembly Side)

*2

AMD Terminal (Fusible Link Assembly Side)

(b) After disconnecting the AMD terminal, wrap it with vinyl insulating tape.

(c) Be sure to reconnect the AMD terminal to the fusible link assembly before reconnecting the cable to the negative (-) terminal of the auxiliary battery.

NOTICE:

A short circuit to ground may occur if the AMD terminal is disconnected before the cable is disconnected from the negative (-) auxiliary battery terminal. If a short circuit to ground occurs, a fusible link or fuse may break.

PRECAUTION FOR DISPOSING OF AN HV BATTERY

(a) When disposing of an HV battery, make sure to return it through an authorized collection agent who is capable of handling it safely. If the HV battery is returned via the manufacturer specified route, it will be returned properly and in a safe manner by an authorized collection agent.

CAUTION:

  • After removing the HV battery, keep it away from water. Exposure to water may cause the HV battery to produce heat, resulting in a fire.
  • Accidents such as electric shock may result if the HV battery is disposed of improperly or abandoned. Therefore, make sure to return all HV batteries through an authorized collection agent.

    *a

    Dealer

    *b

    Battery Collection Agent
  • To reduce the risk of fire, HV battery must not be stored in an area where they will be exposed to fire or high temperatures.
  • If the temperature of the HV battery is high, leave the vehicle until the temperature drops.
  • Make sure to insulate the high-voltage connectors and terminals of the HV battery with insulating tape after removing it.

    If the HV battery stored without insulating the connectors and terminals, electric shock or fire may result.

PRECAUTIONS WHEN REPLACING HYBRID VEHICLE CONTROL ECU

NOTICE:

Before replacing the hybrid vehicle control ECU, refer to Registration.

Click here 2020 MY Corolla Corolla HV [01/2019 - 04/2020]; THEFT DETERRENT / KEYLESS ENTRY: SMART KEY SYSTEM (for Start Function, HV Model): REGISTRATION 2021 - 2022 MY Corolla Corolla HV [04/2020 - 09/2022]; THEFT DETERRENT / KEYLESS ENTRY: SMART KEY SYSTEM (for Start Function, HV Model): REGISTRATION

*1

Cable

*2

Negative (-) Auxiliary Battery Terminal

PRECAUTIONS FOR DISCONNECTING AND RECONNECTING CABLE TO NEGATIVE (-) AUXILIARY BATTERY TERMINAL

(a) Before performing work on electronic components, disconnect the cable from the negative (-) auxiliary battery terminal to prevent damage to the electrical system or electrical components.

(b) Before disconnecting and reconnecting the auxiliary battery cable, turn the power switch off and the headlight switch off. Then loosen the terminal nut completely. Do not damage the cable or terminal.

(c) When the auxiliary battery cable is disconnected, the clock and radio settings and stored DTCs are cleared. Therefore, before disconnecting the auxiliary battery cable, make a note of them.

NOTICE:

  • After turning the power switch off, waiting time may be required before disconnecting the cable from the negative (-) auxiliary battery terminal. Therefore, make sure to read the disconnecting the cable from the negative (-) auxiliary battery terminal notices before proceeding with work.

    Click here 2020 MY Corolla Corolla Hatchback Corolla HV GR Corolla [01/2019 - 03/2019]; INTRODUCTION: REPAIR INSTRUCTION: INITIALIZATION 2020 MY Corolla Corolla Hatchback Corolla HV GR Corolla [03/2019 - 09/2019]; INTRODUCTION: REPAIR INSTRUCTION: INITIALIZATION 2020 MY Corolla Corolla Hatchback Corolla HV GR Corolla [09/2019 - 04/2020]; INTRODUCTION: REPAIR INSTRUCTION: INITIALIZATION 2021 - 2022 MY Corolla Corolla Hatchback Corolla HV GR Corolla [04/2020 - 09/2022]; INTRODUCTION: REPAIR INSTRUCTION: INITIALIZATION

  • When the cable is disconnected from the negative (-) auxiliary battery terminal, initialize the following systems after the cable is reconnected.

    System Name

    See Procedure

    Lane Control System (for HV Model)

    2020 MY Corolla Corolla Hatchback Corolla HV GR Corolla [01/2019 - 03/2019]; INTRODUCTION: REPAIR INSTRUCTION: INITIALIZATION 2020 MY Corolla Corolla Hatchback Corolla HV GR Corolla [03/2019 - 09/2019]; INTRODUCTION: REPAIR INSTRUCTION: INITIALIZATION 2020 MY Corolla Corolla Hatchback Corolla HV GR Corolla [09/2019 - 04/2020]; INTRODUCTION: REPAIR INSTRUCTION: INITIALIZATION 2021 - 2022 MY Corolla Corolla Hatchback Corolla HV GR Corolla [04/2020 - 09/2022]; INTRODUCTION: REPAIR INSTRUCTION: INITIALIZATION

    Pre-collision System (for HV Model)