Toyota RAV4 manuals

Toyota Sienna Service Manual: Push Switch / Key Unlock Warning Switch Malfunction

DTC B2780 Push Switch / Key Unlock Warning Switch Malfunction

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
  • Unlock warning switch assembly
  •  Wire harness
  •  Transponder key ECU assembly

WIRING DIAGRAM

WIRING DIAGRAM

INSPECTION PROCEDURE

1 READ VALUE OF INTELLIGENT TESTER

  1. Connect the intelligent tester (with CAN VIM) to the DLC3.
  2.  Turn the ignition switch on and turn the intelligent tester main switch on.
  3.  Select KEY SW in the DATA LIST and read the value displayed on the intelligent tester.

Transponder key ECU:

Transponder key ECU

OK: ON (Key is in ignition key cylinder) appears on the screen

2 INSPECT UNLOCK WARNING SWITCH ASSEMBLY

 INSPECT UNLOCK WARNING SWITCH ASSEMBLY

  1. Remove the unlock warning switch.
  2. Measure the resistance according to the value(s) in the table below.

Resistance

Resistance

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

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

  1. Disconnect the T6 ECU and K4 switch connectors.
  2.  Measure the resistance according to the value(s) in the table below.

Resistance

Resistance

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

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

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

Resistance

Resistance

REPLACE TRANSPONDER KEY ECU ASSEMBLY

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Other materials:

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