DTC P0703-12: Brake Switch "B" Circuit Short to Battery [06/2018 - 09/2022]: Procedure

1. Connect the Techstream to the DLC3.
2. Turn the engine switch on (IG).
3. Turn the Techstream on.
4. Enter the following menus: Powertrain / Transmission / Data List / Stop Light SW.
5. According to the display on the Techstream, read the Data List while the vehicle is being driven.

   Powertrain > Transmission > Data List 

   Tester Display	Measurement Item	Range	Normal Condition	Diagnostic Note
   Stop Light SW	Stop light switch assembly status	OFF or ON	OFF: Brake pedal released ON: Brake pedal depressed	-

   Powertrain > Transmission > Data List 

   Tester Display
   Stop Light SW

   OK

   On the Techstream screen, ON or OFF is displayed accordingly.

   NOTE:

   In the table above, the conditions listed under "Normal Condition" are reference conditions. Do not depend solely on these reference conditions when deciding whether a part is faulty or not.

   Result

   Proceed to
   OK
   NG

Result: 

OK 

CHECK FOR INTERMITTENT PROBLEMS. Refer to  CHECK FOR INTERMITTENT PROBLEMS [06/2018 - 09/2024] 

Result: 

NG 

See step  2

1. Check the stop light switch assembly installation.

   Refer to INSTALLATION [06/2018 - 01/2019] , or refer to INSTALLATION [01/2019 - ]

   OK

   Stop light switch assembly is installed correctly.

   Result

   Proceed to
   OK
   NG

Result: 

NG 

SECURELY REINSTALL STOP LIGHT SWITCH ASSEMBLY. Refer to  INSTALLATION [06/2018 - 01/2019]  , or refer to  INSTALLATION [01/2019 - ] 

Result: 

OK 

See step  3

1. Inspect the stop light switch assembly.

   Refer to ON-VEHICLE INSPECTION [06/2018 - 01/2019] , or refer to ON-VEHICLE INSPECTION [01/2019 - ]

   Result

   Proceed to
   OK
   NG

Result: 

NG 

REPLACE STOP LIGHT SWITCH ASSEMBLY. Refer to  COMPONENTS [06/2018 - ] 

Result: 

OK 

See step  4

1. Disconnect the C80 TCM connector.

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   *a	Brake pedal depressed	*b	Brake pedal released
   *c	Front view of wire harness connector (to TCM)	-	-

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

   Standard Voltage

   Tester Connection	Condition	Specified Condition
   C80-34 (STP) - Body ground	Brake pedal released	Below 1.5 V
   	Brake pedal depressed	7.5 to 14 V

   Result

   Proceed to
   OK
   NG

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR 

Result: 

OK 

See step  5

1. Replace the TCM.

   Refer to COMPONENTS [06/2018 - 01/2019] , or refer to COMPONENTS [01/2019 - 03/2019] , or refer to COMPONENTS [03/2019 - 09/2024]

   Result

   Proceed to
   NEXT

Result: 

NEXT 

PERFORM REGISTRATION AND INITIALIZATION 

for Registration: Refer to REGISTRATION [06/2018 - 09/2024]

for Initialization: Refer to INITIALIZATION [06/2018 - 09/2022]