Removal [11/2020 - 11/2021]: Procedure

EV battery learning values are stored in the battery ECU assembly and EV control ECU 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 EV battery learning values from the other ECU and stores them.

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NOTE: Do not replace the battery ECU assembly and EV control ECU at the same time as the EV 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 EV control ECU with a used one from another vehicle.

1. Procedure when replacing both battery ECU assembly and EV control ECU:
   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 ignition switch on (READY) and wait for 5 minutes or more.
   5. Turn the ignition 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 ignition switch can be turned on (READY).

      HINT: 

      If the battery ECU assembly and EV control ECU 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.

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NOTE: When replacing the EV control ECU, save and write the stored ion exchanger maintenance distance data.

1. ECU data save

   HINT: 

   This function saves the ion exchanger maintenance distance data stored in the EV control ECU to the GTS.

   1. According to the display on the GTS, save the ion exchanger maintenance distance data to the GTS.

      Powertrain > EV > Utility 

      Tester Display
      ECU Data Save

   2. If the data is not saved to the GTS normally, perform the ion exchanger maintenance distance settings.

      See step  10

Refer to REMOVAL [11/2020 - 11/2021]

Refer to REMOVAL [11/2020 - 11/2021]

1. Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

1. Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

1. Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002