Inspection Procedure

1. Check the DATA LIST for proper functioning of the engine condition.

   Power source control ECU 

   POWER SOURCE CONTROL ECU - DATA LIST REFERENCE
   
   

   Item	Measurement Item / Display (Range)	Normal Condition
   READY SIG	READY condition / ON or OFF or UNKNOWN	ON: Power switch ON (READY) OFF: Power switch ON (IG) / (READY OFF) UNKNOWN: Power switch OFF

   OK: ON (engine (hybrid) running) appears on screen. 

OK: REPLACE POWER SOURCE CONTROL ECU 

NG: GO TO Next Step 

1. Disconnect the K73 ECU connector.
2. Disconnect the A54 ECU connector.
3. Measure the resistance of the wire harness side connectors.

   Standard resistance 

   STANDARD RESISTANCE SPECIFICATION
   
   

   Tester Connection	Specified Condition
   K73-22 (RDY) - A54-117 (RDY)	Below 1 Ω
   K73-22 (RDY) or A54-117 (RDY) -Body ground	10 kΩ or higher

Fig 1: Identifying Power Source Control ECU And HV Control ECU Connector
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK: GO TO Next Step 

1. Measure the voltage of the power source control ECU.

   Standard voltage 

   STANDARD VOLTAGE SPECIFICATION
   
   

   Tester Connection	Condition	Specified Condition
   22 (RDY) - Body ground	Power switch ON (IG) or ON (READY)	Pulse generation (see TERMINALS OF ECU  )

Fig 2: Identifying Power Source Control ECU (Ready Signal)
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

NG:  GO TO HYBRID CONTROL SYSTEM

OK: REPLACE POWER SOURCE CONTROL ECU