Entry Functions do not Operate at All: Description

When the entry functions do not operate at all, it is possible that the certification ECU is malfunctioning or that the wire harness leading to the certification ECU is short-circuited.

1. CHECK KEY CANCEL FUNCTION 
   1. Check that the key cancel function is set.

      OK : key cancel function is set. 

      Key cancel function is set. 

      OK : END (UNSET KEY CANCEL FUNCTION) 

      NG 

2. CHECK WIRE HARNESS (CERTIFICATION ECU ASSEMBLY - BATTERY AND BODY GROUND) 
   1. Disconnect the U28 ECU connector.
   2. Measure the voltage and resistance of the wire harness side connector.

      Standard voltage 

      TESTER CONNECTION SPECIFIED CONDITION
      
      

      Tester Connection	Condition Specified	Condition
      U28-18 (IG) - Body ground	Engine switch off	Below 1 V
      U28-18 (IG) - Body ground	Engine switch on (IG)	10 to 14 V
      U28-1 (+B1) - Body ground	Always	10 to 14 V

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION
      
      

      Tester Connection	Condition Specified	Condition
      U28-17 (E) - Body ground	Always	Below 1 Ω

      Fig 1: Identifying U28 ECU Connector

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      NG : REPAIR OR REPLACE HARNESS AND CONNECTOR 

      OK : REPLACE CERTIFICATION ECU ASSEMBLY