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 assembly does not detect that the unlock warning switch assembly is on even when the ignition switch is ON. Under normal conditions, the unlock warning switch assembly is on when the ignition switch is ON.

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

  • Transponder key ECU assembly

  • Unlock warning switch assembly

  • Harness or connector

WIRING DIAGRAM

A00O4WFE14

INSPECTION PROCEDURE

Note

When replacing the transponder key ECU assembly, refer to the Service Bulletin.

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 ASSEMBLY Click here

    OK

    USE SIMULATION METHOD TO CHECK Click here

  3. INSPECT UNLOCK WARNING SWITCH ASSEMBLY


    1. A00O35V

      Remove the unlock warning switch assembly 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 ASSEMBLY Click here

    OK

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


    1. Disconnect the G3 switch connector.

    2. Disconnect the G138*1 or G74*2 ECU connector.


      • *1: for 5L-E

      • *2: except 5L-E

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

      Standard Resistance
      for 5L-E
      Tester Connection Condition Specified Condition
      G138-3 (KSW) - G3-1 Always Below 1 Ω
      G138-3 (KSW) or G3-1 - Body ground Always 10 kΩ or higher
      G3-2 - Body ground Always Below 1 Ω
      except 5L-E
      Tester Connection Condition Specified Condition
      G74-3 (KSW) - G3-1 Always Below 1 Ω
      G74-3 (KSW) or G3-1 - Body ground Always 10 kΩ or higher
      G3-2 - Body ground Always Below 1 Ω

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

    REPLACE TRANSPONDER KEY ECU ASSEMBLY