Subaru Impreza 2002 Service Manual page 3510

3. CHECK VEHICLE SPEED SENSOR
Step
1 CHECK VEHICLE SPEED SENSOR.
1)Lift-up the vehicle and support it with safety
stands.
2)Remove the combination meter with harness
connector.
Warning:
Be careful not to get caught in the running
wheels.
3)Drive the vehicle at a speed greater than 20
km/h (12 MPH).
4)Measure the voltage between combination
meter connector and chassis ground.
Connector & terminal
(i10) No. 2 (+) — Chassis ground ( − − − − ):
2 CHECK VEHICLE SPEED SENSOR POWER
SUPPLY.
1)Turn the ignition switch to OFF.
2)Disconnect the vehicle speed sensor har-
ness connector.
3)Turn the ignition switch to ON.
4)Measure the voltage between vehicle speed
sensor connector and engine ground.
Connector & terminal
(B17) No. 3 (+) — Engine ground ( − − − − ):
3 CHECK HARNESS BETWEEN VEHICLE
SPEED SENSOR AND ENGINE GROUND.
1)Turn the ignition switch to OFF.
2)Measure the resistance between vehicle
speed sensor connector and engine ground.
Connector & terminal
(B17) No. 2 (+) — Engine ground ( − − − − ):
4 CHECK HARNESS BETWEEN VEHICLE
SPEED SENSOR AND COMBINATION
METER.
1)Disconnect the connector from combination
meter.
2)Measure the resistance between vehicle
speed sensor harness connector and combi-
nation meter harness connector.
Connector & terminal
(B17) No. 1 — (i10) No. 2:
COMBINATION METER SYSTEM
Is the voltage less than 1V
←→ more than 4 V?
Is the voltage more than 10 V? Go to step 3.
Is the resistance less than 10
Ω?
Is the resistance less than 10
Ω?
IDI-7
INSTRUMENTATION/DRIVER INFO
Check
Check the speed-
ometer. <Ref. to
IDI-17,
REMOVAL,
Speedometer.>
Go to step 4.
Replace the vehi-
cle speed sensor.
Yes No
Go to step 2.
Check the harness
for open or short
between ignition
switch and vehicle
speed sensor.
Repair the wiring
harness.
Repair the wiring
harness.