Inspection Procedure

1. NO: GO TO STEP   3 
2. YES: GO TO NEXT STEP 

1. Turn the ignition switch ON with the key that does not start the engine.
2. ECU DATA MONITOR
   1. Inspect with LEXUS hand-held tester (ECU data monitor)

IMMOBILIZER ECU (TRANSPONDER KEY ECU ASSEMBLY) (SWITCH CONDITION) 

1. OK: NORMALITY 
2. NG: GO TO NEXT STEP 

1. Check whether the engine starts with the other keys for the vehicle.

1. OK: RE-REGISTER OR REPLAY KEY THAT DOES NOT START ENGINE 
2. NG: GO TO NEXT STEP 

1. Check the continuity between terminal of the transponder key coil connector.

Standard: 

Fig 1: Identifying Transponder Key Coil Connector

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

1. NG: REPAIR OR REPLACE TRANSPONDER KEY COIL 
2. OK: GO TO NEXT STEP 

1. Disconnect the transponder key amplifier and transponder key ECU connectors.
2. Check the continuity between each terminal of the transponder key amplifier vehicles side connector and the transponder key ECU vehicles side connector. See TERMINALS OF ECU .

   Standard: 

   SPECIFIED CONDITION
   
   

   Terminals (Amplifier - ECU)	Specified condition
   T12-1 <=> T13-9 (+B <=> VC12)	Continuity
   T12-4 <=> T13-12 (TXCT <=> TXCT)	Continuity
   T12-2 <=> T13-10 (CODE <=> CODE)	Continuity
   T12-3 <=> T13-11 (RXCK <=> RXCK)	Continuity
   T12-5 <=> T13-13 (GND <=> AGND)	Continuity

3. Check the continuity between each terminal of the transponder key amplifier vehicles side connector or the transponder key ECU vehicles side connector and body ground. See TERMINALS OF ECU .

   Standard: 

   SPECIFIED CONDITION
   
   

   Terminals (Amplifier - ECU)	Specified condition
   T12-1 or T13-9 <=> Body ground (+B or VC12 <=> Body ground)	No continuity
   T12-4 or T13-12 <=> Body ground (TXCT or TXCT <=> Body ground)	No continuity
   T12-2 or T13-10 <=> Body ground (CODE or CODE <=> Body ground)	No continuity
   T12-3 or T13-11 <=> Body ground (RXCK or RXCK <=> Body ground)	No continuity
   T12-5 or T13-13 <=> Body ground (GND or AGND o Body ground)	No continuity

   Fig 2: Identifying Wire Harness Transponder Key Amplifier - Transponder Key ECU

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

1. NG: REPAIR OR REPLACE WIRE HARNESS OR CONNECTOR 
2. OK: GO TO NEXT STEP. 

1. After exchanging the transponder key ECU, check that the engine starts.

1. NG: REPLACE TRANSPONDER KEY ECU ASSEMBLY 
2. OK: NORMAL (TRANSPONDER KEY AMPLIFIER DETECTIVE)