ECU Power Source Circuit [12/2017 - 10/2023]: Procedure

1. Measure the voltage according to the value(s) in the table below.

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   *a	Front view of wire harness connector (to Sub-battery Module Assembly)

   Standard Voltage

   Tester Connection	Condition	Specified Condition
   P6-7 (B) - Body ground	Engine switch off	11 to 14 V

   Result

   Proceed to
   OK
   NG

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR (BATTERY - SUB-BATTERY MODULE ASSEMBLY) 

Result: 

OK 

See step  2

1. Disconnect the sub-battery module assembly connector.
2. Turn the engine switch on (IG).
3. Measure the voltage according to the value(s) in the table below.

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   *a	Rear view of wire harness connector (to Sub-battery Module Assembly)

   Standard Voltage

   Tester Connection	Condition	Specified Condition
   P6-14 (IG) - Body ground	Engine switch on (IG)	11 to 14 V

4. Reconnect the sub-battery module assembly connector.

   Result

   Proceed to
   OK
   NG

Result: 

OK 

CHECK FOR INTERMITTENT PROBLEMS. Refer to  CHECK FOR INTERMITTENT PROBLEMS [12/2017 - 10/2023] 

Result: 

NG 

See step  3

1. Remove the LUG-IG NO. 1 relay from the No. 2 luggage room relay block.
2. Disconnect the sub-battery module assembly connector.
3. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   LUG-IG NO. 1 relay terminal 5 - P6-14 (IG)	Always	Below 1 Ω
   LUG-IG NO. 1 relay terminal 5 or P6-14 (IG) - Body ground and other terminals	Always	10 kΩ or higher

   Result

   Proceed to
   OK
   NG

Result: 

OK 

GO TO SMART ACCESS SYSTEM WITH PUSH-BUTTON START (FOR START FUNCTION). Refer to  Power Source Mode does not Change to ON (IG and ACC) [12/2017 - 10/2023] 

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR