ENGINE IMMOBILISER SYSTEM (w/o Smart 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 key is in the ignition key cylinder. Under normal conditions, the unlock warning switch assembly is ON when the key is in the ignition key cylinder.

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

  • Unlock warning switch assembly

  • Transponder key ECU assembly

 Insert the door control transmitter assembly 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

B000L7NE01

INSPECTION PROCEDURE

Note


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

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

PROCEDURE


  1. CLEAR DTC


    1. Clear the DTCs Click here.


    NEXT

  2. CHECK FOR DTC


    1. Perform "DTC Output Confirmation Operation" procedure.

    2. Check for DTCs Click here.

      OK
      DTC B2780 is not output.
      Result
      Result Proceed to
      DTC B2780 is output A
      DTC B2780 is not output B

    B

    USE SIMULATION METHOD TO CHECK Click here

    A

  3. INSPECT UNLOCK WARNING SWITCH ASSEMBLY


    1. B000NQAE04
      Text in Illustration
      *a

      Component without harness connected

      (Unlock Warning Switch Assembly)
      *b Free
      *c Pushed

      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 Condition Specified Condition
      1 - 2

      Pushed

      (Key set)

      		 Below 1 Ω
      1 - 2

      Free

      (Key removed)

      		 10 kΩ or higher

    NG

    REPLACE UNLOCK WARNING SWITCH ASSEMBLY Click here

    OK

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


    1. Disconnect the I19 transponder key ECU assembly connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      I19-3 (KSW) - I33-1 (UN+) Always Below 1 Ω
      I19-3 (KSW) or I33-1 (UN+) - Body ground Always 10 kΩ or higher
      I33-2 (UN-) - Body ground Always Below 1 Ω

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

    REPLACE TRANSPONDER KEY ECU ASSEMBLY