LIGHTING SYSTEM, Diagnostic DTC:B124E

DTC Code DTC Name
B124E Flasher Relay Circuit

DESCRIPTION

This DTC is stored when the main body ECU detects malfunctions in the turn signal flasher relay circuit.

DTC Code DTC Detection Condition Trouble Area
B124E Malfunction in turn signal flasher relay circuit

  • Turn signal flasher

  • Main body ECU

  • Harness or connector

  • Headlight dimmer switch

WIRING DIAGRAM

A01EMWUE02

INSPECTION PROCEDURE

Note

Inspect the fuses for circuits related to this system before performing the following inspection procedure.

PROCEDURE


  1. CLEAR DTC


    1. Clear the DTCs Click here.


    NEXT

  2. CHECK DTC


    1. Operate the turn signal switch to cause the left and right turns signal lights to each blink for 3 seconds or more.

    2. Check for DTCs Click here.

      OK
      DTC B124E is not output.

    NG

    READ VALUE USING INTELLIGENT TESTER (TURN SIGNAL SWITCH) Click here

    OK

    USE SIMULATION METHOD TO CHECK Click here

  3. READ VALUE USING INTELLIGENT TESTER (TURN SIGNAL SWITCH)


    1. Using the intelligent tester, read the Data List Click here.

      Main Body
      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Right LaneChgFlas Turn Signal Switch Turn signal switch (right lane change position) signal / ON or OFF

      ON: Turn signal switch moved to the right lane change position

      OFF: Turn signal switch off

      		 -
      Left LaneChgFlas Turn Signal Switch Turn signal switch (left lane change position) signal / ON or OFF

      ON: Turn signal switch moved to the left lane change position

      OFF: Turn signal switch off

      		 -
      R or L TurnFlas Turn Signal Switch (Auto Off) Turn signal switch (left or right) signal / ON or OFF

      ON: Turn signal switch moved to the left or right position

      OFF: Turn signal switch off

      		 -
      OK
      When the headlight dimmer switch (turn signal switch) operation is performed, the result will be the same as above.

    NG

    INSPECT HEADLIGHT DIMMER SWITCH (TURN SIGNAL SWITCH) Click here

    OK

  4. CHECK HARNESS AND CONNECTOR (TURN SIGNAL FLASHER - BATTERY AND BODY GROUND)


    1. A01EO7UE09

      Disconnect the E19 flasher connector.

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      E19-4 (B) - Body ground Always 11 to 14 V
      E19-1 (IG) - Body ground Engine switch on (IG) 11 to 14 V

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      E19-7 (E) - Body ground Always Below 1 Ω

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  5. CHECK HARNESS AND CONNECTOR (MAIN BODY ECU - TURN SIGNAL FLASHER)


    1. Disconnect the E2 and E4 ECU connectors.

      A01ERG0E04

    2. Disconnect the E19 flasher connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      E4-9 (HZCT) - E19-3 (LL) Always 1 MΩ or higher*1
      Approximately 1 Ω*2
      E4-9 (HZCT) - E19-2 (LR) Always 1 MΩ or higher*1
      Approximately 1 Ω*2
      E2-26 (TRNL) - E19-5 (EL) Always Below 1 Ω
      E2-4 (TRNR) - E19-6 (ER) Always Below 1 Ω
      E2-26 (TRNL) - Body ground Always 10 kΩ or higher
      E2-4 (TRNR) - Body ground Always 10 kΩ or higher

      Tech Tips

      *1: Measure the resistance by connecting the positive (+) tester probe to terminal E4-9 (HZCT) and the negative (-) tester probe to terminal E19-3 (LL) or E19-2 (LR).

      *2: Measure the resistance by connecting the positive (+) tester probe to terminal E19-3 (LL) or E19-2 (LR) and the negative (-) tester probe to terminal E4-9 (HZCT). Use this value only as a reference, as the resistance varies depending on the measurement instrument.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  6. CHECK TURN SIGNAL FLASHER


    1. for LHD:


      1. Temporarily replace the turn signal flasher with a new or normally functioning one Click here.

    2. for RHD:


      1. Temporarily replace the turn signal flasher with a new or normally functioning one Click here.

    3. Operate the turn signal switch to cause the left and right turns signal lights to each blink for 3 seconds or more.

    4. Check for DTCs Click here.

      OK
      DTC B124E is not output.

    NG

    REPLACE MAIN BODY ECU

    OK

    END (TURN SIGNAL FLASHER WAS DEFECTIVE)

  7. INSPECT HEADLIGHT DIMMER SWITCH (TURN SIGNAL SWITCH)


    1. for LHD:


      1. Remove the headlight dimmer switch Click here.

        A01EQX0E09

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

        Standard Resistance
        Tester Connection Switch Condition Specified Condition
        13 (TR) - 12 (EL) Turn signal switch right turn Below 1 Ω
        Turn signal switch off 10 kΩ or higher
        14 (CR) - 12 (EL) Turn signal switch right turn Below 1 Ω
        Turn signal switch left turn Below 1 Ω
        Turn signal switch off 10 kΩ or higher
        15 (TL) - 12 (EL) Turn signal switch left turn Below 1 Ω
        Turn signal switch off 10 kΩ or higher

    2. fro RHD:


      1. Remove the headlight dimmer switch Click here.

        A01ER6LE09

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

        Standard Resistance
        Tester Connection Switch Condition Specified Condition
        16 (TR) - 19 (EL) Turn signal switch right turn Below 1 Ω
        Turn signal switch off 10 kΩ or higher
        17 (CR) - 19 (EL) Turn signal switch right turn Below 1 Ω
        Turn signal switch left turn Below 1 Ω
        Turn signal switch off 10 kΩ or higher
        18 (TL) - 19 (EL) Turn signal switch left turn Below 1 Ω
        Turn signal switch off 10 kΩ or higher
        Result
        Result Proceed to
        OK A
        NG (for LHD) B
        NG (for RHD) C

    B

    REPLACE HEADLIGHT DIMMER SWITCH Click here

    C

    REPLACE HEADLIGHT DIMMER SWITCH Click here

    A

  8. CHECK HARNESS AND CONNECTOR (HEADLIGHT DIMMER SWITCH - MAIN BODY ECU AND BODY GROUND)


    1. Disconnect the E14 switch connector.

      A01ES2LE02

    2. Disconnect the E1 and E3 ECU connectors.

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

      Standard Resistance
      for LHD
      Tester Connection Condition Specified Condition
      E3-3 (TRI) - E14-13 (TR) Always Below 1 Ω
      E1-20 (TLI) - E14-15 (TL) Always Below 1 Ω
      E3-2 (CNRI) - E14-14 (CR) Always Below 1 Ω
      E14-12 (EL) - Body ground Always Below 1 Ω
      E3-3 (TRI) - Body ground Always 10 kΩ or higher
      E1-20 (TLI) - Body ground Always 10 kΩ or higher
      E3-2 (CNRI) - Body ground Always 10 kΩ or higher
      for RHD
      Tester Connection Condition Specified Condition
      E3-3 (TRI) - E14-16 (TR) Always Below 1 Ω
      E1-20 (TLI) - E14-18 (TL) Always Below 1 Ω
      E3-2 (CNRI) - E14-17 (CR) Always Below 1 Ω
      E14-19 (EL) - Body ground Always Below 1 Ω
      E3-3 (TRI) - Body ground Always 10 kΩ or higher
      E1-20 (TLI) - Body ground Always 10 kΩ or higher
      E3-2 (CNRI) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

    REPLACE MAIN BODY ECU