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 assembly

  • Main body ECU

  • Harness or connector

WIRING DIAGRAM

A01GWN7E08

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

    PERFORM ACTIVE TEST USING GTS (TURN SIGNAL LIGHT) Click here

    OK

    NORMAL

  3. PERFORM ACTIVE TEST USING GTS (TURN SIGNAL LIGHT)


    1. Using the GTS, perform the Active Test.

      Tester Display Test Part Control Range Diagnostic Note
      Turn Light RH Relay Operation Turn signal light operation OFF / ON -
      Turn Light LH Relay Operation Turn signal light operation OFF / ON -
      OK
      Turn signal light condition is switched by Active Test.

    NG

    CHECK HARNESS AND CONNECTOR (TURN SIGNAL FLASHER - BATTERY AND BODY GROUND) Click here

    OK

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


    1. A01GWUBE02

      Disconnect the A68 ECU connector.

    2. Disconnect the L125 flasher connector.

    3. Disconnect the B1 or B11 headlight connector.

    4. Disconnect the N10 or N1 front multiplex network door ECU connector.

    5. Disconnect the S51 or S52 rear combination light connector.

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

      Standard resistance
      Tester Connection Condition Specified Condition
      A68-9 (HZCT) - L125-3 (LL) Always 1 MΩ or higher*1
      Approximately 300 kΩ*2
      A68-9 (HZCT) - L125-2 (LR) Always 1 MΩ or higher*1
      Approximately 300 kΩ*2
      A68-9 (HZCT) - Body ground Always 10 kΩ or higher

      Tech Tips

      *1: Measure the resistance by connecting the positive (+) tester probe to terminal A68-9 (HZCT) and the negative (-) tester probe to terminal L125-3 (LL) or L125-2 (LR).

      *2: Measure the resistance by connecting the positive (+) tester probe to terminal L125-3 (LL) or L125-2 (LR) and the negative (-) tester probe to terminal A68-9 (HZCT). Use this value only as a reference, as the resistance varies between several hundred and several hundred thousand ohms depending on the measurement instrument.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

    REPLACE MAIN BODY ECU

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


    1. A01H0DRE07

      Disconnect the L125 flasher connector.

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

      Standard resistance
      Tester Connection Condition Specified Condition
      L125-7 (E) - Body ground Always Below 1 Ω

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

      Standard voltage
      Tester Connection Switch Condition Specified Condition
      L125-4 (B) - Body ground Always 11 to 14 V
      L125-1 (IG) - Body ground Power switch on (IG) 11 to 14 V

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

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


    1. A01GWFME02

      Disconnect the A68 and DA ECU connectors.

    2. Disconnect the L125 flasher connector.

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

      Standard resistance
      Tester Connection Condition Specified Condition
      A68-9 (HZCT) - L125-3 (LL) Always 1 MΩ or higher*1
      Approximately 300 kΩ*2
      A68-9 (HZCT) - L125-2 (LR) Always 1 MΩ or higher*1
      Approximately 300 kΩ*2
      DA-55 (TRNL) - L125-5 (EL) Always Below 1 Ω
      DA-56 (TRNR) - L125-6 (ER) Always Below 1 Ω
      DA-55 (TRNL) - Body ground Always 10 kΩ or higher
      DA-56 (TRNR) - Body ground Always 10 kΩ or higher

      Tech Tips

      *1: Measure the resistance by connecting the positive (+) tester probe to terminal A68-9 (HZCT) and the negative (-) tester probe to terminal L125-3 (LL) or L125-2 (LR).

      *2: Measure the resistance by connecting the positive (+) tester probe to terminal L125-3 (LL) or L125-2 (LR) and the negative (-) tester probe to terminal A68-9 (HZCT). Use this value only as a reference, as the resistance varies between several hundred and several hundred thousand ohms depending on the measurement instrument.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  7. CHECK TURN SIGNAL FLASHER ASSEMBLY (OPERATION)


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

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

    3. Check for DTCs Click here.

      OK
      DTC B124E is not output.

    NG

    REPLACE MAIN BODY ECU

    OK

    REPLACE TURN SIGNAL FLASHER ASSEMBLY Click here