SUB BATTERY SYSTEM, Diagnostic DTC:B2302

DTC Code DTC Name
B2302 Communication Error from Sub Battery Module to Backup Relay

DESCRIPTION

Backup relay malfunctions cannot be detected on the sub-battery module assembly side. Therefore, information about a backup relay input malfunction that is detected on the backup relay ECU side is sent to the sub-battery module assembly, which outputs this DTC.

B000X6FE02
DTC No. Detection Item DTC Detection Condition Trouble Area Warning Indicate Memory
B2302 Communication Error from Sub Battery Module to Backup Relay

This DTC is stored when a malfunction is detected in communication from the sub-battery module assembly to the backup relay.

(3 trip detection logic)

  • Harness or connector

  • Backup relay

  • Sub-battery module assembly

 Comes on DTC stored

Tech Tips

The details of a DTC can be checked by using the DTC Sub Code of the freeze frame data that was recorded when the DTC was output.

DTC Sub Code Detail
"38" Waveform malfunction in sub-battery module assembly signal line (BUR) continuously occurs for 15 seconds
"39" Short to ground in sub-battery module assembly signal line (BUR) continuously occurs for 10 seconds

WIRING DIAGRAM

B000YXMC01
*a BUR
*b Backup Relay
*c Sub-battery Module Assembly

CONFIRMATION DRIVING PATTERN


  1. Connect the GTS to the DLC3.

  2. Turn the engine switch on (IG) and turn the GTS on.

  3. Clear the DTCs.

    Click here

  4. Turn the engine switch off and wait for at least 30 seconds.

  5. Turn the engine switch on (IG) and wait for at least 20 seconds or more. (A)

  6. Turn the engine switch off and wait for at least 30 seconds. (B)

  7. Repeat steps (A) through (B) shown above at least 3 times.

  8. Turn the engine switch on (IG).

  9. Turn the GTS on.

  10. Enter the following menus: Body Electrical / Sub Battery Module / Trouble Codes.

  11. Check the DTC.

    Click here

    Tech Tips

    If a DTC is output, the system is malfunctioning.

CAUTION / NOTICE / HINT

Tech Tips

Read freeze frame data using the GTS. Freeze frame data records the sub battery module condition when malfunctions are detected.

PROCEDURE


  1. CHECK CONNECTOR CONNECTION CONDITION (SUB-BATTERY MODULE ASSEMBLY)


    1. B000TYZ

      Check the connection condition of the sub-battery module assembly connector and the contact pressure of the terminal. Check the terminals for deformation, and check the connector for water ingress and foreign matter.

      OK
      - The connector is connected securely.
      - The terminals are not deformed and are connected securely.
      - No water or foreign matter in each connector.
      Result
      Result Proceed to
      OK A
      NG (The connector is not connected securely.) B
      NG (The terminals are not making secure contact or are deformed, or water or foreign matter exists in a connector.) C

    B

    CONNECT SECURELY

    C

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    A

  2. CHECK CONNECTOR CONNECTION CONDITION (BACKUP RELAY)


    1. B000VYS

      Check the connection condition of the backup relay connector and the contact pressure of the terminal. Check the terminals for deformation, and check the connector for water ingress and foreign matter.

      OK
      - The connector is connected securely.
      - The terminals are not deformed and are connected securely.
      - No water or foreign matter in each connector.
      Result
      Result Proceed to
      OK A
      NG (The connector is not connected securely.) B
      NG (The terminals are not making secure contact or are deformed, or water or foreign matter exists in a connector.) C

    B

    CONNECT SECURELY

    C

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    A

  3. CHECK DTC OUTPUT


    1. Connect the GTS to the DLC3.

    2. Turn the engine switch on (IG).

    3. Turn the GTS on.

    4. Clear the DTCs.


      Body Electrical > Sub Battery Module > Clear DTCs

    5. Turn the engine switch off and wait for at least 30 seconds.

    6. Turn the engine switch on (IG) and wait for at least 20 seconds or more. (A)

    7. Turn the engine switch off and wait for at least 30 seconds. (B)

    8. Repeat steps (A) through (B) shown above at least 3 times.

    9. Turn the engine switch on (IG).

    10. Turn the GTS on.

    11. Enter the following menus: Body Electrical / Sub Battery Module / Trouble Codes.


      Body Electrical > Sub Battery Module > Trouble Codes

    12. Read the DTCs.

      Result
      Result Proceed to
      DTC B2302 is output A
      DTC B2303 and B2304 are output B
      DTC is not output C

    B

    REPAIR OR REPLACE HARNESS OR CONNECTOR (BACKUP RELAY - SUB-BATTERY MODULE ASSEMBLY)

    C

    END

    A

  4. CHECK FREEZE FRAME DATA (DTC SUB CODE)


    1. Check the DTC sub code displayed in the freeze frame data.

      Result
      Result Proceed to
      "38" is output A
      "39" is output B

    B

    INSPECT BACKUP RELAY Click here

    A

  5. INSPECT SUB-BATTERY MODULE ASSEMBLY


    1. Turn the engine switch on (IG).

    2. B000XNFC03
      *a Reference waveform duty ratio: 78 to 82%

      Inspect the sub-battery module assembly using an oscilloscope.

      Sub Battery Module Terminal Name b5-8 (BUR) - m1-1 (-BAT)
      Tester Range 5 V/DIV., 10 msec./DIV.
      Condition Engine switch on (IG)
      Result
      Result Proceed to
      Duty ratio of normal waveform is 58 to 62% or 78 to 82% A
      No pulse waveforms or pulse output except those listed above B

    B

    REPLACE SUB-BATTERY MODULE ASSEMBLY Click here

    A

  6. CHECK HARNESS AND CONNECTOR (SUB-BATTERY MODULE ASSEMBLY - BACKUP RELAY)


    1. Disconnect the sub-battery module assembly connector.

    2. Disconnect the backup relay connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      b5-8 (BUR) - 5D-1 (RLY1) Always Below 1 Ω
      b5-8 (BUR) or 5D-1 (RLY1) - Body ground and other terminals Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE BACKUP RELAY Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

  7. INSPECT BACKUP RELAY


    1. Disconnect the sub-battery module assembly connector

    2. Turn the engine switch on (IG).

    3. B000Y5FC07
      *a

      Rear view of wire harness connector

      (to Sub-battery Module Assembly)

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      b5-8 (BUR) - Body ground Engine switch on (IG) 8 to 14 V

    4. Reconnect the sub-battery module assembly connector

      Result
      Proceed to
      OK
      NG

    OK

    REPLACE SUB-BATTERY MODULE ASSEMBLY Click here

    NG

  8. CHECK HARNESS AND CONNECTOR (SUB-BATTERY MODULE ASSEMBLY - BACKUP RELAY)


    1. Disconnect the sub-battery module connector.

    2. Disconnect the backup relay connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      b5-8 (BUR) - 5D-1 (RLY1) Always Below 1 Ω
      b5-8 (BUR) or 5D-1 (RLY1) - Body ground and other terminals Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE BACKUP RELAY Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR