ECU Power Source Circuit: Procedure

1. Remove the TEL and IGN fuses from the engine room relay block.
2. Remove the ACC fuse from the cowl side junction block LH.
3. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   TEL fuse	Always	Below 1 Ω
   IGN fuse	Always	Below 1 Ω
   ACC fuse	Always	Below 1 Ω

NG → REPLACE FUSE 

OK: Go to next step 

1. Disconnect the P2 ECU connector.
   Fig 1: Identifying P2 ECU Connector End View Terminal

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Measure the voltage and resistance according to the value(s) in the table below.

   Standard Voltage

   Tester Connection	Switch Condition	Specified Condition
   P2-1 (+B) - Body ground	Always	11 to 14 V
   P2-13 (IG2) - Body ground	Engine switch on (IG)	11 to 14 V
   	Engine switch off	Below 1 V
   P2-14 (ACC) - Body ground	Engine switch on (ACC)	11 to 14 V
   	Engine switch off	Below 1 V

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   P2-12 (E) - Body ground	Always	Below 1 Ω

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK: Go to next step 

NEXT → See step   4