Power Source Mode does not Change to ON (IG) [12/2021 - ]: Procedure

1. Using the GTS, check for certification ECU (smart key ECU assembly) DTCs.

   Body Electrical > Power Source Control > Trouble Codes 

   Body Electrical > Smart Access > Trouble Codes 

   Result

   Result	Proceed to
   DTCs are not output	A
   Smart access system with push-button start (for Start Function) DTCs are output	B

Result: 

B 

GO TO DIAGNOSTIC TROUBLE CODE CHART. Refer to  DIAGNOSTIC TROUBLE CODE CHART [12/2021 - ] 

Result: 

A 

See step  2

1. Disconnect the I40 certification ECU (smart key ECU assembly) connector.
2. Disconnect the 5B and 5C power distribution box assembly connectors.
3. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   I40-24 (IGPD) - 5C-17	Always	Below 1 Ω
   I40-11 (IGRD) - 5B-11	Always	Below 1 Ω
   5B-36 - Body ground	Always	Below 1 Ω
   I40-24 (IGPD) or 5C-17 - Other terminals and body ground	Always	10 kΩ or higher
   I40-11 (IGRD) or 5B-11 - Other terminals and body ground	Always	10 kΩ or higher

   Result

   Proceed to
   OK
   NG

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR 

Result: 

OK 

See step  3

1. Connect the I40 certification ECU (smart key ECU assembly) connector.

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   *a	Component with harness connected (Certification ECU (Smart Key ECU Assembly))

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

   Standard Voltage

   Tester Connection	Switch Condition	Specified Condition
   I40-11 (IGRD) - Body ground	Ignition switch ACC → Ignition switch ON	1 V or less → 9 V or higher
   I40-24 (IGPD) - Body ground	Ignition switch ACC → Ignition switch ON	1 V or less → 9 V or higher

   Result

   Proceed to
   OK
   NG

Result: 

NG 

REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY). Refer to  REMOVAL [12/2021 - ] 

Result: 

OK 

See step  4

1. Disconnect the I40 certification ECU (smart key ECU assembly) connector.
2. Disconnect the 5B, 5C and 5K power distribution box assembly connectors.
3. Measure the voltage according to the value(s) in the table below.

   Standard Voltage

   Tester Connection	Condition	Specified Condition
   5K-1 - Body ground	Always	11 to 14 V

   Result

   Proceed to
   OK
   NG

Result: 

OK 

REPLACE POWER DISTRIBUTION BOX ASSEMBLY. Refer to  REMOVAL [12/2021 - ] 

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR