Meter / Gauge System Speedometer Malfunction

DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

CHECK VEHICLE SPEED SENSOR (INPUT SIGNAL)

CHECK HARNESS AND CONNECTOR (VEHICLE SPEED SENSOR - COMBINATION METER ASSEMBLY AND BODY GROUND)

DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

1. Remove the combination meter assembly with the connector(s) still connected.
   

2. Using an oscilloscope, check the signal waveform of the meter.
   

   Measurement Condition

   Item	Content
   Tester Connection	C27-5 (SI) - Body ground
   Tool Setting	5 V/DIV., 20 msec./DIV.
   Condition	Driving at approx. 20 km/h (12 mph)

   Text in Illustration

   *a	Component with harness connected (Combination Meter Assembly)

   OK:

   The waveform displayed is as shown in the illustration.
   

   HINT:

   As the vehicle speed increases, the wavelength shortens.

1. Disconnect the S3 vehicle speed sensor connector.
   

2. Disconnect the C27 combination meter assembly connector.
   

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

   Standard Resistance:

   Tester Connection	Condition	Specified Condition
   C27-5 (SI) - S3-3 (SI)	Always	Below 1 Ω
   C27-31 (MS5) - S3-1 (IG+)	Always	Below 1 Ω
   S3-1 (IG+) - S3-2 (SE)	Always	10 kΩ or higher
   S3-1 (IG+) - S3-3 (SI)	Always	10 kΩ or higher
   S3-2 (SE) - S3-3 (SI)	Always	10 kΩ or higher
   S3-2 (SE) - Body ground	Always	Below 1 Ω