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.

Detection Item

DTC Detection Condition

Trouble Area

Note

B2780

Push Switch / Key Unlock Warning Switch Malfunction

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

  • DTC Output Confirmation Operation:

  • Insert the key into the ignition key cylinder.

  • *: Only output while a malfunction is present.

Table 1. Vehicle Condition and Fail-safe Operation when Malfunction Detected

Vehicle Condition when Malfunction Detected

Fail-safe Operation when Malfunction Detected

Engine cannot be started

-
Table 2. Related Data List and Active Test

DTC No.

Data List and Active Test

B2780

Key SW

WIRING DIAGRAM

B278950E05

CAUTION / NOTICE / HINT

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.

      Body Electrical > Immobiliser > Clear DTCs

    Result

    Proceed to

    NEXT
    NEXT

  2. CHECK FOR DTC

    1. Check for DTCs.

      Body Electrical > Immobiliser > Trouble Codes

      Tip:

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

      OK

      DTC B2780 is not output.

    Result

    Result

    Proceed to

    B2780 is not output

    A

    B2780 is output

    B

  3. INSPECT UNLOCK WARNING SWITCH ASSEMBLY

    1. Remove the unlock warning switch assembly.

      Click here

    2. Inspect the unlock warning switch assembly.

      Click here

    Result

    Proceed to

    OK

    NG
    NG

    REPLACE UNLOCK WARNING SWITCH ASSEMBLY

    Click here

    OK

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

    1. Disconnect the E5 unlock warning switch assembly connector.

    2. Disconnect the E21 transponder key ECU assembly connector.

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

      Standard Resistance

      Tester Connection

      Condition

      Specified Condition

      E5-1 - E21-3 (KSW)

      Always

      Below 1 Ω

      E5-2 - Body ground

      Always

      Below 1 Ω

      E5-1 - Body ground

      Always

      10 kΩ or higher

      E21-3 (KSW) - Body ground

      Always

      10 kΩ or higher

    Result

    Proceed to

    OK

    NG
    OK

    REPLACE TRANSPONDER KEY ECU ASSEMBLY

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR