Dtc B2780 Push Switch / Key Unlock Warning Switch Malfunction

Vehicle Interior. Corolla. Zre142 Aze141
Theft Deterrent Keyless Entry. Corolla. Zre142 Aze141

DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

READ VALUE USING TECHSTREAM

INSPECT UNLOCK WARNING SWITCH ASSEMBLY

CHECK HARNESS AND CONNECTOR (UNLOCK WARNING SWITCH - BODY GROUND)

CHECK HARNESS AND CONNECTOR (TRANSPONDER KEY ECU - UNLOCK WARNING SWITCH)

DTC B2780 Push Switch / Key Unlock Warning Switch Malfunction


DESCRIPTION

This DTC will be output if the transponder key ECU assembly does not detect that the unlock warning switch 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 No.
DTC Detection Condition
Trouble Area
B2780
"Unlock warning switch ON" is not detected when ignition switch is ON
  1. Wire harness or connector
  2. Unlock warning switch assembly
  3. Transponder key ECU assembly

WIRING DIAGRAM


Corolla. Zre142 Aze141.Theft Deterrent Keyless Entry.Smart Key System (For Entry Function). Dtc B2780 Push Switch / Key Unlock Warning Switch Malfunction


INSPECTION PROCEDURE

NOTICE:
If the transponder key ECU assembly is replaced, register the key and ECU communication ID (COROLLA_ZRE142 RM00000120Y02CX.html).
1.READ VALUE USING TECHSTREAM

  1. Connect the Techstream to the DLC3.

  1. Turn the ignition switch to ON.

  1. Turn the Techstream on.

  1. Enter the following menus: Body Electrical / Immobiliser / Data List.

  1. Read the Data List according to the display on the Techstream.

    Immobiliser (Transponder Key ECU Assembly)
    Tester Display
    		Measurement Item/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:
    On the Techstream screen, the item changes between ON and OFF according to the chart above.


NG
Go to step 2
OK

REPLACE TRANSPONDER KEY ECU ASSEMBLY (COROLLA_ZRE142 RM000003G05004X.html)

2.INSPECT UNLOCK WARNING SWITCH ASSEMBLY


    Corolla. Zre142 Aze141.Theft Deterrent Keyless Entry.Smart Key System (For Entry Function). Dtc B2780 Push Switch / Key Unlock Warning Switch Malfunction

  1. Remove the unlock warning switch assembly (COROLLA_ZRE142 RM0000026TU02HX.html).

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

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


NG
REPLACE UNLOCK WARNING SWITCH ASSEMBLY (COROLLA_ZRE142 RM0000026TU02HX.html)
OK


3.CHECK HARNESS AND CONNECTOR (UNLOCK WARNING SWITCH - BODY GROUND)


    Corolla. Zre142 Aze141.Theft Deterrent Keyless Entry.Smart Key System (For Entry Function). Dtc B2780 Push Switch / Key Unlock Warning Switch Malfunction

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

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    E5-2 - Body ground
    		Always
    		Below 1 Ω


NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


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


    Corolla. Zre142 Aze141.Theft Deterrent Keyless Entry.Smart Key System (For Entry Function). Dtc B2780 Push Switch / Key Unlock Warning Switch Malfunction

  1. Disconnect the transponder key ECU assembly connector.

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

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    E21-3 (KSW) - E5-1
    		Always
    		Below 1 Ω
    E5-1 - Body ground
    		Always
    		10 kΩ or higher


NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

REPLACE TRANSPONDER KEY ECU ASSEMBLY (COROLLA_ZRE142 RM000003G05004X.html)