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.

DTC No. DTC Detection Condition Trouble Area DTC Output Confirmation Operation
B2780 The unlock warning switch assembly is not detected as being on when the ignition switch is ON (1 trip detection logic*).

  • Wire harness or connector

  • Un-lock warning switch Assembly

  • Transponder key ECU assembly

 Insert the key into the ignition key cylinder.

Vehicle Condition and Fail-safe Operation when Malfunction Detected
Vehicle Condition when Malfunction Detected Fail-safe Operation when Malfunction Detected
Engine cannot be started -
Related Data List and Active Test
DTC No. Data List and Active Test
B2780 Key SW

WIRING DIAGRAM

A005KREE04
*a Un-lock Warning Switch Assembly
*b Transponder Key ECU Assembly

CAUTION / NOTICE / HINT

Note


  • If the transponder key ECU assembly is replaced, refer to the Service Bulletin.

  • After repair, confirm that no DTCs are output by performing "DTC Output Confirmation Operation".

  • When using the GTS with the vehicle ignition switch off, connect the GTS to the vehicle and turn a courtesy light switch on and off at intervals of 1.5 seconds or less until communication between the GTS and the vehicle begins. Then select the Model Code "KEY REGIST" under manual mode and enter the following menus: Body Electrical / Immobiliser. While using the GTS, periodically turn a courtesy light switch on and off at intervals of 1.5 seconds or less to maintain communication between the GTS and the vehicle.

PROCEDURE


  1. CLEAR DTC


    1. Clear the DTCs Click here.


    NEXT

  2. CHECK FOR DTC


    1. Check the DTCs Click here.

      Tech Tips

      Before checking for DTCs, perform the "DTC Output Confirmation Operation" procedure.

      OK
      DTC B2780 is not output.

    OK

    USE SIMULATION METHOD TO CHECK Click here

    NG

  3. INSPECT UN-LOCK WARNING SWITCH ASSEMBLY


    1. Remove the un-lock warning switch assembly Click here.

    2. Inspect the un-lock warning switch assembly Click here.


    NG

    REPLACE UN-LOCK WARNING SWITCH ASSEMBLY Click here

    OK

  4. CHECK HARNESS AND CONNECTOR (UN-LOCK WARNING SWITCH ASSEMBLY - BODY GROUND)


    1. Disconnect the F54 transponder key ECU assembly connector.

    2. Disconnect the F15 un-lock warning switch assembly connector.

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

      Standard Resistance (Check for Open)
      Tester Connection Condition Specified Condition
      F54-3 (KSW) - F15-1 Always Below 1 Ω
      F15-2 - Body ground Always Below 1 Ω
      Standard Resistance (Check for Short)
      Tester Connection Condition Specified Condition
      F54-3 (KSW) or F15-1 - Body ground Always 10 kΩ or higher

    OK

    REPLACE TRANSPONDER KEY ECU ASSEMBLY

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR