ENGINE IMMOBILISER SYSTEM (w/o Entry and Start System), Diagnostic DTC:B2780

DTC Code DTC Name
B2780 Push Switch / Key Unlock Warning Switch Malfunction

DESCRIPTION

This DTC is stored if the transponder key ECU does not detect that the unlock warning switch is on even when the ignition switch is ON. Under normal conditions, the unlock warning switch is on when the ignition switch is ON.

DTC Code DTC Detection Condition Trouble Area
B2780 The unlock warning switch is not detected as being on when the ignition switch is ON.

  • Transponder key ECU

  • Unlock warning switch

  • Harness or connector

WIRING DIAGRAM

A01ISBWE12

INSPECTION PROCEDURE

Note

When the transponder key ECU is replaced, reregister the ECU - ECM communication ID.

PROCEDURE


  1. CLEAR DTC


    1. Clear the DTCs Click here.


    NEXT

  2. CHECK FOR DTC


    1. Check for DTCs Click here.

      OK
      DTC B2780 is not output.

    NG

    INSPECT UNLOCK WARNING SWITCH Click here

    OK

    USE SIMULATION METHOD TO CHECK Click here

  3. INSPECT UNLOCK WARNING SWITCH


    1. A01IN1IE05

      Remove the unlock warning switch Click here.

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      1 - 2 Pushed Below 1 Ω
      Not pushed 10 kΩ or higher

    NG

    REPLACE UNLOCK WARNING SWITCH Click here

    OK

  4. CHECK HARNESS AND CONNECTOR (UNLOCK WARNING SWITCH - BODY GROUND)


    1. A01IQ8ZE12
      Text in Illustration
      *1

      Front view of wire harness connector

      (to Unlock Warning Switch)

      Disconnect the H7 switch connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      H7-2 - Body ground Always Below 1 Ω

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  5. CHECK HARNESS AND CONNECTOR (UNLOCK WARNING SWITCH - TRANSPONDER KEY ECU)


    1. A01IRGEE21
      Text in Illustration
      *1

      Front view of wire harness connector

      (to Unlock Warning Switch)
      *2

      Front view of wire harness connector

      (to Transponder Key ECU)

      Disconnect the H7 switch connector.

    2. Disconnect the H110 ECU connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      H110-3 (KSW) - H7-1 Always Below 1 Ω
      H110-3 (KSW) or H7-1 - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

    REPLACE TRANSPONDER KEY ECU