HYBRID BATTERY SYSTEM, Diagnostic DTC:U029A-123

DTC Code DTC Name
U029A-123 Lost Communication with Hybrid Battery Pack Sensor Module

DESCRIPTION

The battery smart unit detects the HV battery conditions (voltage, current, and temperature) and the battery cooling fan voltage, and sends the detected signals to the power management control ECU via the serial communication system.

DTC No. DTC Detection Condition Trouble Area
U029A-123 Problem in serial communication between the battery smart unit and power management control ECU (1 trip detection)

  • Wire harness or connector

  • Power management control ECU

  • Battery smart unit

WIRING DIAGRAM

A003S7XE01

INSPECTION PROCEDURE

CAUTION:


  • If the battery cover is removed, install it before turning the power switch on (IG) or (READY). If the power switch is turned on (IG) or (READY) with the battery cover removed, U029A-123 may be set.

  • Before inspecting the high-voltage system, take safety precautions to prevent electrical shocks, such as wearing insulated gloves and removing the service plug grip. 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.

  • After removing the service plug grip, wait for at least 10 minutes before touching any of the high-voltage connectors or terminals. After waiting for 10 minutes, check the voltage at the terminals in the inspection point in the inverter with converter assembly. The voltage should be 0 V before beginning work Click here.

Tech Tips

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

PROCEDURE


  1. CHECK DTC OUTPUT (HV)


    1. Connect the intelligent tester to the DLC3.

    2. Turn the power switch on (IG).

    3. Enter the following menus: Powertrain / Hybrid Control / Trouble Codes.

    4. Check if DTCs are output.

      Result
      Result Proceed to
      P0AFC-123 is not output. A
      P0AFC-123 is also output. B

    5. Turn the power switch off.


    B

    GO TO DTC CHART Click here

    A

  2. CHECK WAVEFORM

    CAUTION:

    Be sure to wear insulated gloves.


    1. Check that the service plug grip is not installed.

      Note

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

    2. Remove the No. 1 hybrid vehicle battery carrier bracket sub-assembly Click here.

    3. Turn the power switch on (IG).

    4. A003RJOE02
      Text in Illustration
      *a

      Component with harness connected

      (Battery Smart Unit)

      Connect an oscilloscope between the battery smart unit terminals specified in the table below, and measure the waveform.

      Item Content
      Tester Connection

      CH1: d1-2 (BTH+) - d1-8 (GND)

      CH2: d1-3 (BTH-) - d1-8 (GND)
      Equipment Setting 2 V/DIV., 500 μs/DIV.
      Condition Power switch on (IG)

      Note

      Turning the power switch on (IG) with the service plug grip removed causes an interlock switch system DTC to be set. Use the intelligent tester to clear the DTCs Click here.

      Result
      Result Proceed to
      Constant approximately 0 V. A
      Constant approximately 5 V. B
      Waveform peak 11 to 14 V. C

    5. Turn the power switch off.

    6. Install the No. 1 hybrid vehicle battery carrier bracket sub-assembly Click here.


    B

    CHECK HARNESS AND CONNECTOR (POWER MANAGEMENT CONTROL ECU - BATTERY SMART UNIT) Click here

    C

    CHECK HARNESS AND CONNECTOR (+B SHORT) Click here

    A

  3. CHECK HARNESS AND CONNECTOR (GND SHORT)

    CAUTION:

    Be sure to wear insulated gloves.


    1. Check that the service plug grip is not installed.

      Note

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

    2. A003T3UE01
      Text in Illustration
      *1 Power Management Control ECU

      Disconnect connector E111 from the power management control ECU Click here.

    3. Remove the No. 1 hybrid vehicle battery carrier bracket sub-assembly Click here.

    4. A003TSJE07

      Disconnect connector d1 from the battery smart unit.

    5. A003T1XE02
      Text in Illustration
      *a

      Rear view of wire harness connector

      (to Battery Smart Unit)

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      d1-2 (BTH+) - d1-8 (GND) and Body ground Power switch off 10 kΩ or higher
      d1-3 (BTH-) - d1-8 (GND) and Body ground Power switch off 10 kΩ or higher

    6. Connect the battery smart unit connector.

    7. Install the No. 1 hybrid vehicle battery carrier bracket sub-assembly Click here.

    8. Connect the power management control ECU connector Click here.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  4. CHECK BATTERY SMART UNIT

    CAUTION:

    Be sure to wear insulated gloves.


    1. Check that the service plug grip is not installed.

      Note

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

    2. Remove the No. 1 hybrid vehicle battery carrier bracket sub-assembly Click here.

    3. A003TSJE07

      Disconnect connector d1 from the battery smart unit.

    4. Turn the power switch on (IG).

    5. A003T1XE02
      Text in Illustration
      *a

      Rear view of wire harness connector

      (to Battery Smart Unit)

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

      Note

      Turning the power switch on (IG) with the service plug grip removed causes an interlock switch system DTC to be set. Use the intelligent tester to clear the DTCs Click here.

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      d1-2 (BTH+) - d1-8 (GND) Power switch on (IG) approximately 5 V
      d1-3 (BTH-) - d1-8 (GND) Power switch on (IG) approximately 5 V

    6. Connect the battery smart unit connector.

    7. Install the No. 1 hybrid vehicle battery carrier bracket sub-assembly Click here.


    NG

    REPLACE POWER MANAGEMENT CONTROL ECU Click here

    OK

    REPLACE BATTERY SMART UNIT Click here

  5. CHECK HARNESS AND CONNECTOR (POWER MANAGEMENT CONTROL ECU - BATTERY SMART UNIT)

    CAUTION:

    Be sure to wear insulated gloves.


    1. Check that the service plug grip is not installed.

      Note

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

    2. A003T3UE01
      Text in Illustration
      *1 Power Management Control ECU

      Disconnect connector E111 from the power management control ECU Click here.

    3. Remove the No. 1 hybrid vehicle battery carrier bracket sub-assembly Click here.

    4. A003TSJE07

      Disconnect connector d1 from the battery smart unit.

    5. A003RM6E02
      Text in Illustration
      *a

      Rear view of wire harness connector

      (to Power Management Control ECU)
      *b

      Rear view of wire harness connector

      (to Battery Smart Unit)

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      E111-32 (BTH+) - d1-2 (BTH+) Power switch off Below 1 Ω
      E111-33 (BTH-) - d1-3 (BTH-) Power switch off Below 1 Ω

      Note

      When taking a measurement with a tester, do not apply excessive force to the tester probe to avoid damaging the holder.

    6. Connect the battery smart unit connector.

    7. Install the No. 1 hybrid vehicle battery carrier bracket sub-assembly Click here.

    8. Connect the power management control ECU connector Click here.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

    REPLACE BATTERY SMART UNIT Click here

  6. CHECK HARNESS AND CONNECTOR (+B SHORT)

    CAUTION:

    Be sure to wear insulated gloves.


    1. Check that the service plug grip is not installed.

      Note

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

    2. A003TBXE01
      Text in Illustration
      *1 Power Management Control ECU

      Disconnect connectors A99 and E111 from the power management control ECU Click here.

    3. Remove the No. 1 hybrid vehicle battery carrier bracket sub-assembly Click here.

    4. A003TSJE07

      Disconnect connector d1 from the battery smart unit.

    5. A003RRME01
      Text in Illustration
      *a

      Rear view of wire harness connector

      (to Power Management Control ECU)

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      E111-32 (BTH+) - E111-1 (AM22) Power switch off 10 kΩ or higher
      E111-32 (BTH+) - A99-5 (+B1) Power switch off 10 kΩ or higher
      E111-33 (BTH-) - E111-1 (AM22) Power switch off 10 kΩ or higher
      E111-33 (BTH-) - A99-5 (+B1) Power switch off 10 kΩ or higher

      Note

      When taking a measurement with a tester, do not apply excessive force to the tester probe to avoid damaging the holder.

    6. Connect the battery smart unit connector.

    7. Install the No. 1 hybrid vehicle battery carrier bracket sub-assembly Click here.

    8. Connect the power management control ECU connectors Click here.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  7. CHECK POWER MANAGEMENT CONTROL ECU

    CAUTION:

    Be sure to wear insulated gloves.


    1. Check that the service plug grip is not installed.

      Note

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

    2. Remove the No. 1 hybrid vehicle battery carrier bracket sub-assembly Click here.

    3. A003TSJE07

      Disconnect connector d1 from the battery smart unit.

    4. Turn the power switch on (IG).

    5. A003T1XE02
      Text in Illustration
      *a

      Rear view of wire harness connector

      (to Battery Smart Unit)

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

      Note

      Turning the power switch on (IG) with the service plug grip removed causes an interlock switch system DTC to be set. Use the intelligent tester to clear the DTCs Click here.

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      d1-2 (BTH+) - d1-8 (GND) Power switch on (IG) approximately 5 V
      d1-3 (BTH-) - d1-8 (GND) Power switch on (IG) approximately 5 V

    6. Turn the power switch off.

    7. Connect the battery smart unit connector.

    8. Install the No. 1 hybrid vehicle battery carrier bracket sub-assembly Click here.


    NG

    REPLACE POWER MANAGEMENT CONTROL ECU Click here

    OK

    REPLACE BATTERY SMART UNIT Click here