Main Switch Circuit [10/2016 - 09/2020]: 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 / ASC / Data List.
5. Read the Data List according to the display on the Techstream.

   Body Electrical > ASC > Data List 

   Tester Display	Measurement Item	Range	Normal Condition	Diagnostic Note
   Volume SW	Vehicle sound switch on/off status	OFF or ON	OFF: Vehicle sound switch off ON: Vehicle sound switch on	-

   Body Electrical > ASC > Data List 

   Tester Display
   Volume SW

   OK

   Normal conditions listed above are displayed.

   Result

   Proceed to
   OK
   NG

Result: 

OK 

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE. Refer to  PROBLEM SYMPTOMS TABLE [10/2016 - 09/2020] 

Result: 

NG 

See step  2

1. Check the vehicle sound switch on/off operation.

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   *a	Component without harness connected (Vehicle Sound Switch)
   *b	Switch Indicator

   1. Remove the vehicle sound switch.

      Refer to REMOVAL [10/2016 - 09/2020]

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

      Standard Resistance

      Tester Connection	Condition	Specified Condition
      3 (NVI) - 8 (NVS)	Vehicle sound switch on	Below 1 Ω
      3 (NVI) - 8 (NVS)	Vehicle sound switch off	10 kΩ or higher

2. Inspect the switch indicator.
   1. Apply battery voltage to the vehicle sound switch connector and check that the switch indicator comes on.

      OK

      Measurement Condition	Condition	Specified Condition
      Battery positive (+) → 8 (NVS) Battery negative (-) → 4 (E)	Vehicle sound switch on	Switch indicator comes on

   Result

   Proceed to
   OK
   NG

Result: 

NG 

REPLACE VEHICLE SOUND SWITCH. Refer to  REMOVAL [10/2016 - 09/2020] 

Result: 

OK 

See step  3

1. Disconnect the K154 stereo component equalizer assembly connector.
2. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   K155-3 (NVI) - K154-5 (VLSW)	Always	Below 1 Ω
   K155-3 (NVI) - Body ground	Always	10 kΩ or higher
   K155-4 (E) - Body ground	Always	Below 1 Ω

   Result

   Proceed to
   OK
   NG

Result: 

OK 

REPLACE STEREO COMPONENT EQUALIZER ASSEMBLY. Refer to  REMOVAL [10/2016 - 09/2020] 

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR