DTC    B2780    Push Switch / Key Unlock Warning Switch Malfunction

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DESCRIPTION

This DTC will be output if the transponder key ECU does not detect that the unlock warning switch is on even when the ignition switch is on (Under the normal conditions, the unlock warning switch is on when the ignition switch is on).

DTC No.
DTC Detection Condition
Trouble Area
B2780
Unlock warning switch on is not detected when ignition switch is on
  1. Unlock warning switch assembly
  2. Wire harness
  3. Transponder key ECU assembly

WIRING DIAGRAM


B111589E03


INSPECTION PROCEDURE

1.READ VALUE OF INTELLIGENT TESTER

  1. Connect the intelligent tester to the DLC3.

  1. Turn the ignition switch on and turn the intelligent tester main switch on.

  1. Select Key SW in the DATA LIST and read the value displayed on the intelligent tester.

    Transponder key ECU: 
    Item
    		Measurement Item/Display (Range)
    		Normal Condition
    		Diagnostic Note
    Key SW
    		Unlock warning switch signal /ON or OFF
    		ON: Key is in ignition key cylinder
    OFF: No key is in ignition key cylinder
    		-

    OK:
    Both ON (Key is in ignition key cylinder) and OFF (No key in ignition key cylinder) appear on the screen.



OK
REPLACE TRANSPONDER KEY ECU ASSEMBLY
NG


2.INSPECT UNLOCK WARNING SWITCH ASSEMBLY


    B111614E01

  1. Remove the unlock warning switch.

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

    Resistance:
    Tester Connection
    		Switch Condition
    		Specified Condition
    1 - 2
    		Switch pushed (Key set)
    		Below 1 Ω
    Switch free (Key removed)
    		10 kΩ or higher



NG
REPLACE UNLOCK WARNING SWITCH ASSEMBLY
OK


3.CHECK HARNESS AND CONNECTOR (TRANSPONDER KEY ECU ASSEMBLY - UNLOCK WARNING SW ASSEMBLY)


    B111594E03

  1. Disconnect the T8 ECU and K6 switch connectors.

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

    Resistance:
    Tester Connection
    		Specified Condition
    T8-3 (KSW) - K6-2
    		Below 1 Ω
    T8-3 (KSW) - Body ground
    		10 kΩ or higher



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


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


    B111599E03

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

    Resistance:
    Tester Connection
    		Specified Condition
    K6-1 - Body ground
    		Below 1 Ω



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

REPLACE TRANSPONDER KEY ECU ASSEMBLY