DTC P1779-49: Gear Shift Control Module Backup Power Supply Internal Electronic Failure [10/2023 - ]: Procedure

1. Disconnect the L291 integration control supply connector.
2. Remove the P CON MTR2 relay from the No. 2 luggage room relay block assembly.
3. Measure the voltage according to the value(s) in the table below.

   Standard Voltage

   Tester Connection	Condition	Specified Condition
   L291-19 (BUA) - Body ground	Always	Below 1 V

4. Install the P CON MTR2 relay.
5. Reconnect the L291 integration control supply connector.

   Result

   Proceed to
   OK
   NG

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR 

Result: 

OK 

See step  2

1. Disconnect the L291 integration control supply connector.
2. Disconnect the G81 shift control ECU connector.
3. Measure the voltage according to the value(s) in the table below.

   Standard Voltage

   Tester Connection	Condition	Specified Condition
   L291-1 (BUSE) - Body ground	Always	Below 1 V

4. Reconnect the G81 shift control ECU connector.
5. Reconnect the L291 integration control supply connector.

   Result

   Proceed to
   OK
   NG

Result: 

OK 

REPLACE INTEGRATION CONTROL SUPPLY. Refer to  REMOVAL [10/2023 - ] 

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR