Subaru Forester 2004 Service Manual page 122

Diagnostics Procedure with Diagnostic Trouble Code (DTC)
Step
1 CHECK IF THE WHEELS HAVE TURNED
FREELY FOR A LONG TIME.
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
Check if the wheels have been
turned freely for more than one
minute, such as when vehicle
is jacked-up, under full-lock
cornering or when tire is not in
contact with road surface.
Did the wheels turn 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 tightend
33 N·m (3.4 kgf-m, 24.6 ft-lb)
Is the gap the 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-121
ABS (DIAGNOSTIC)
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 vehicle is
towed or jacked-
up, or when steer-
ing wheel is contin-
uously turned all
way, this trouble
code may some-
times occur.
Go to step 3. Replace the tire.
Replace the tire. Go to step 4.
Go to step 5. Adjust the tire
pressure.
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 spacers can-
not correct gap, re-
place worn ABS
wheel speed sen-
sor or worn tone
wheel.
Go to step 8. Go to step 9.
No