Key Lock-in Prevention Function does not Work Properly: Procedure

1. Check the DATA LIST for proper functioning of the unlock warning switch.
   IMMOBILISER
   
   

   Tester Display	Measurement Item/Range	Normal Condition	Diagnostic Note
   Key SW	Key unlock warning switch signal / ON or OFF	ON: Key is in ignition key cylinder OFF: No key is in ignition key cylinder	-

   OK

   "ON" (Key is in ignition key cylinder) appears on the screen.

NG → See step   6 

OK: Go to next step 

1. Check the DATA LIST for proper functioning of the courtesy switch.
   DRIVER DOOR
   
   

   Tester Display	Measurement Item/Range	Normal Condition	Diagnostic Note
   Courtesy SW	Door courtesy switch signal / ON or OFF	ON: Door is open OFF: Door is closed	-

NG → See step   3 

OK → REPLACE MULTIPLEX NETWORK FRONT DOOR ECU LH 

1. Disconnect the D8 switch connector.
   Fig 1: Identifying D8 And D21 Connectors

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Disconnect the D21 ECU connector.
3. Measure the resistance of the wire harness side connectors.

   Standard resistance

   Tester Connection	Specified Condition
   D8-1 (+) - D21-27 (CTY)	Below 1 Ω
   D8-1 (+) - Body ground	10 kΩ or higher
   D21-27 (CTY) - Body ground	10 kΩ or higher

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK: Go to next step 

1. Measure the resistance of the switch.
   Fig 2: Identifying Front Door Courtesy Switch Assembly (Driver Side)

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   Standard resistance

   Tester Connection	Switch Condition	Specified Condition
   1- Body ground	Not pushed (ON)	Below 1 Ω
   1- Body ground	Pushed (OFF)	10 kΩ or higher

NG → REPLACE FRONT DOOR COURTESY LIGHT SWITCH ASSEMBLY LH 

OK → REPLACE MULTIPLEX NETWORK FRONT DOOR ECU LH 

1. Remove the unlock warning switch.
   Fig 3: Identifying Unlock Warning Switch Connector Terminals

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Measure the resistance of the switch.

   Standard resistance

   Tester Connection	Switch Condition	Specified Condition
   1 - 2	Not pushed	10 kΩ or higher
   1 - 2	Pushed	Below 1 Ω

NG → REPLACE UNLOCK WARNING SWITCH ASSEMBLY 

OK: Go to next step 

Fig 4: Identifying U1 Switch Connector Terminals

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

1. Disconnect the U1 switch connector.
2. Disconnect the T13 ECU connector.
3. Measure the resistance of the wire harness side connectors.

   Standard resistance

   Tester Connection	Specified Condition
   U1-1 - Body ground	Below 1 Ω
   U1-2 - T13-3 (KSW)	Below 1 Ω

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK → REPLACE TRANSPONDER KEY ECU