Inspection Procedure

1. Check that the key cancel function is set.

   OK: 

   Key cancel function is set. 

OK: END (UNSET KEY CANCEL FUNCTION) 

NG: Go to next step 

1. Disconnect the U28 ECU connector.
2. Measure the voltage and resistance of the wire harness side connector.

   Standard voltage 

   VOLTAGE SPECIFICATION
   
   

   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 

   RESISTANCE SPECIFICATION
   
   

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

Fig 1: Identifying U28 ECU Connector Terminals

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

NG: REPAIR OR REPLACE HARNESS AND CONNECTOR 

OK: REPLACE CERTIFICATION ECU ASSEMBLY