Speed Signal Circuit [10/2015 - ]: Procedure

1. The circuits that send vehicle speed signals to this system are inspected in the meter section (Refer to Speed Signal Circuit [10/2015 - ] ).
2. During inspection of the meter system, if there is an instruction that indicates to go back to inspections for the lighting system, proceed to the next step.

Result: 

NEXT 

See step  2

1. Disconnect the D9 combination meter assembly connector.
2. Disconnect the A24 headlight leveling ECU assembly connector.
3. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   A24-16 (SPDR) - D9-9 (+S)	Always	Below 1 Ω

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR 

Result: 

OK 

See step  3

1. Check the output waveform.

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   TEXT IN ILLUSTRATION
   
   

   *a

   Component with harness connected (Combination Meter Assembly)

   -

   -

   1. Remove the combination meter assembly with the connector still connected.
   2. Connect an oscilloscope to terminal D9-9 (+S) and body ground.
   3. Turn the power switch on (IG).
   4. Check the signal waveform according to the condition(s) in the table below.

      Item	Condition
      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: 

OK 

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE 

(Refer to PROBLEM SYMPTOMS TABLE [10/2014 - ] )

Result: 

NG 

REPLACE COMBINATION METER ASSEMBLY 

(Refer to REMOVAL [10/2014 - ] )