Subaru Impreza 2003 Service Manual page 2402

DIAGNOSTICS PROCEDURE WITHOUT DIAGNOSTIC TROUBLE CODE (DTC)
ABS (DIAGNOSTICS)
Step
1 CHECK IF THE WHEELS HAVE TURNED
FREELY FOR A LONG TIME.
Check if the wheels have been turned freely for
more than 1 minute, such as when vehicle is
jacked-up, under full-lock cornering or when
tire is not in contact with road surface.
2 CHECK TIRE SPECIFICATIONS.
Turn the ignition switch to OFF.
3 CHECK WEAR OF TIRE.
4 CHECK TIRE PRESSURE.
5 CHECK INSTALLATION OF ABS WHEEL
SPEED SENSOR.
6 CHECK ABS WHEEL SPEED SENSOR GAP.
Measure the tone wheel to ABS wheel speed
sensor piece gap over entire perimeter of the
wheel.
7 PREPARE OSCILLOSCOPE.
Check
Have the wheels been turned
freely?
Are the tire specifications cor-
rect?
Is the tire worn excessively?
Is the tire pressure correct?
Are the ABS wheel speed sen-
sor installation bolts tightened
33 N·m (3.3 kgf-m, 24 ft-lb)?
Is the gap as following value?
Front wheel:
0.3 — 0.8 mm (0.012 — 0.031
in)
Rear wheel:
0.7 — 1.2 mm (0.028 — 0.047
in)
Is an oscilloscope available?
ABS-62
Yes
The ABS is nor- Go to step 2.
mal. Erase the
DTC.
NOTE:
When the wheels
turn freely for a
long time, such as
when the vehicle is
towed or jacked-
up, or when steer-
ing wheel is contin-
uously turned all
the way, this DTC
may sometimes
occur.
Go to step 3. Replace the tire.
Replace tire. Go to step 4.
Go to step 5. Adjust tire pres-
sure.
Go to step 6. Tighten the ABS
wheel speed sen-
sor installation
bolts securely.
Go to step 7. Adjust the gap.
NOTE:
Adjust the gap us-
ing spacer (Part
No. 26755AA000).
If the spacer can-
not correct gap, re-
place worn sensor
or worn
wheel.
Go to step 8. Go to step 9.
No
tone