Vehicle Speed Signal Circuit between Stereo Component Amplifier and Combination Meter [09/2015 - 08/2019]: Procedure

1. Check the output waveform.

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   *a	Component with harness connected (Combination Meter Assembly)

   1. Remove the combination meter assembly with the connector(s) still connected.
   2. Connect an oscilloscope to terminal J10-19 (+S) and body ground.
   3. Turn the engine switch on (IG).
   4. Turn a wheel slowly.
   5. Check the signal waveform according to the condition(s) in the table below.

      Item	Condition
      Measurement terminal	J10-19 (+S) - Body ground
      Tool setting	5 V/DIV., 20 ms./DIV.
      Vehicle condition	Wheel being rotated

      OK

      The waveform is similar to that shown in the illustration.

      HINT: 

      When the system is functioning normally, one wheel revolution generates 4 pulses. As the vehicle speed increases, the width indicated by (A) in the illustration narrows.

   Result

   Proceed to
   OK
   NG

Result: 

NG 

GO TO METER / GAUGE SYSTEM. Refer to  Speed Signal Circuit [09/2015 - 08/2019] 

Result: 

OK 

See step  2

1. Check the input waveform.

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   *a	Component with harness connected (Stereo Component Amplifier Assembly)

   1. Remove the stereo component amplifier assembly with the connector(s) still connected.
   2. Connect an oscilloscope to terminal J66-17 (SPD) and body ground.
   3. Turn the engine switch on (IG).
   4. Turn a wheel slowly.
   5. Check the signal waveform according to the condition(s) in the table below.

      Item	Condition
      Measurement terminal	J66-17 (SPD) - Body ground
      Tool setting	5 V/DIV., 20 ms./DIV.
      Vehicle condition	Wheel being rotated

      OK

      The waveform is similar to that shown in the illustration.

      HINT: 

      When the system is functioning normally, one wheel revolution generates 4 pulses. As the vehicle speed increases, the width indicated by (A) in the illustration narrows.

   Result

   Proceed to
   OK
   NG

Result: 

OK 

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE. Refer to  PROBLEM SYMPTOMS TABLE [09/2015 - 12/2017]  , or refer to  PROBLEM SYMPTOMS TABLE [12/2017 - 08/2019] 

Result: 

NG 

See step  3

1. Disconnect the J10 combination meter assembly connector.
2. Disconnect the J118 junction connector.
3. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   J10-19 (+S) - J118-21	Always	Below 1 Ω

   Result

   Proceed to
   OK
   NG

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR 

Result: 

OK 

See step  4

1. Disconnect the J66 stereo component amplifier assembly connector.
2. Disconnect the J118 junction connector.
3. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   J66-17 (SPD) - J118-17	Always	Below 1 Ω

   Result

   Proceed to
   OK
   NG

Result: 

OK 

REPAIR OR REPLACE JUNCTION CONNECTOR 

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR