Inspection Procedure

1. Disconnect the K73 ECU connector.
2. Disconnect the A6 ECM connector.
3. Measure the resistance of the wire harness side connectors.

   Standard resistance 

   TESTER CONNECTION SPECIFIED CONDITION CHART
   
   

   Tester Connection	Specified Condition
   K73-39 (STSW) - A6-19 (STSW)	Below 1 Ω
   K73-39 (STSW) or A6-19 (STSW) - Body ground	10 kΩ or higher

Fig 1: Identifying K73 ECU And A6 ECM Connectors

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

NG: REPAIR OR REPLACE HARNESS AND CONNECTOR 

OK: Go to next step 

1. Temporarily replace the power source control ECU with a new or normally functioning one.
2. Check that the engine starts normally.

   OK: 

   Engine starts normally. 

NG: GO TO  SFI SYSTEM

OK: REPLACE POWER SOURCE CONTROL ECU