Main Switch Circuit [09/2014 - 01/2023]: 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: Body Electrical / Blind Spot Monitor Master / Data List.
5. Read the Data List according to the display on the Techstream.

   Body Electrical > Blind Spot Monitor Master > Data List 

   Tester Display	Measurement Item	Range	Normal Condition	Diagnostic Note
   Main Switch	State of the blind spot monitor main switch (warning canceling switch assembly)	OFF or ON	OFF: Blind spot monitor main switch (warning canceling switch assembly) off ON: Blind spot monitor main switch (warning canceling switch assembly) on	-

   Body Electrical > Blind Spot Monitor Master > Data List 

   Tester Display
   Main Switch

   Result

   Result	Proceed to
   The display does not change as shown above when the blind spot monitor main switch (warning canceling switch assembly) is operated.	A
   The display changes as shown above when the blind spot monitor main switch (warning canceling switch assembly) is operated.	B

Result: 

B 

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE. Refer to  PROBLEM SYMPTOMS TABLE [09/2014 - 03/2019]  , or refer to  PROBLEM SYMPTOMS TABLE [03/2019 - ] 

Result: 

A 

See step  2

1. Remove the blind spot monitor main switch (warning canceling switch assembly).

   Refer to REMOVAL [09/2014 - 01/2023]

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

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   *a	Component without harness connected (Blind Spot Monitor Main Switch (Warning Canceling Switch Assembly))

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   8 (B) - 11 (D)	Blind spot monitor main switch on (not protruding)	Below 25 Ω
   8 (B) - 11 (D)	Blind spot monitor main switch off (protruding)	1 MΩ or higher

   Result

   Proceed to
   OK
   NG

Result: 

NG 

REPLACE BLIND SPOT MONITOR MAIN SWITCH (WARNING CANCELING SWITCH ASSEMBLY). Refer to  REMOVAL [09/2014 - 01/2023] 

Result: 

OK 

See step  3

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

   Standard Voltage

   Tester Connection	Condition	Specified Condition
   O99-8 (B) - Body ground	Engine switch on (IG)	11 to 14 V
   O99-8 (B) - Body ground	Engine switch off	Below 1 V

   Result

   Proceed to
   OK
   NG

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR 

Result: 

OK 

See step  4

1. Disconnect the U48 blind spot monitor sensor LH connector.
2. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   U48-8 (BSSW) - O99-11 (D)	Always	Below 1 Ω
   U48-8 (BSSW) - Body ground	Always	10 kΩ or higher

   Result

   Proceed to
   OK
   NG

Result: 

OK 

REPLACE BLIND SPOT MONITOR SENSOR LH. Refer to  REMOVAL [09/2014 - 03/2019]  , or refer to  REMOVAL [03/2019 - ] 

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR