Subaru 2002 IMPREZA Service Manual page 2209

DIAGNOSTICS CHART WITH SUBARU SELECT MONITOR
Step
11 CHECK ABS SENSOR SIGNAL.
1)Raise all four wheels off ground.
2)Turn the ignition switch to OFF.
3)Connect the oscilloscope to the connector.
4)Turn the ignition switch to ON.
5)Rotate the wheels and measure voltage at
specified frequency. <Ref. to ABS-17, WAVE-
FORM, Control Module I/O Signal.>
NOTE:
When this inspection is completed, the
ABSCM&H/U sometimes stores DTC 29.
Connector & terminal
DTC 22 /
LHD: (B15) No. 1 (+) — No. 2 ( − − − − ):
RHD: (F95) No. 1 (+) — No. 2 ( − − − − ):
DTC 24 /
(F94) No. 1 (+) — No. 2 ( − − − − ):
DTC 26 /
LHD: (B99) No. 9 (+) — No. 10 ( − − − − ):
RHD: (B99) No. 20 (+) — No. 21 ( − − − − ):
DTC 28 /
LHD: (B99) No. 4 (+) — No. 5 ( − − − − ):
RHD: (B99) No. 8 (+) — No. 9 ( − − − − ):
12 CHECK CONTAMINATION OF ABS SENSOR
OR TONE WHEEL.
Remove the disc rotor or drum from hub in
accordance with DTC.
13 CHECK DAMAGE OF ABS SENSOR OR
TONE WHEEL.
14 CHECK TONE WHEEL RUNOUT.
Measure the tone wheel runout.
15 CHECK RESISTANCE OF ABS SENSOR.
1)Turn the ignition switch to OFF.
2)Disconnect the connector from ABS sensor.
3)Measure the resistance between ABS sen-
sor connector terminals.
Terminal
Front RH No. 1 — No. 2:
Front LH No. 1 — No. 2:
Rear RH No. 1 — No. 2:
Rear LH No. 1 — No. 2:
Check
Is the oscilloscope pattern
smooth, as shown in the fig-
ure?
Is the ABS sensor piece or
tone wheel contaminated by
dirt or other foreign matter?
Are there broken or damaged
in the ABS sensor piece or
tone wheel?
Is the runout less than 0.05
mm (0.0020 in)?
Is the resistance between 1
and 1.5 kΩ?
ABS-111
ABS (DIAGNOSTICS)
Yes
Go to step 15. Go to step 12.
Thoroughly Go to step 13.
remove dirt or
other foreign mat-
ter.
Replace the ABS Go to step 14.
sensor or tone
wheel. Front:
<Ref. to ABS-14,
Front ABS Sen-
sor.> Rear: <Ref.
to ABS-17, Rear
ABS Sensor.> and
Front: <Ref. to
ABS-20, Front
Tone Wheel.>
Rear: <Ref. to
ABS-21, Rear
Tone Wheel.>
Go to step 15. Replace the tone
wheel. Front:
<Ref. to ABS-20,
Front Tone
Wheel.> Rear:
<Ref. to ABS-21,
Rear Tone
Wheel.>
Go to step 16. Replace the ABS
sensor. Front:
<Ref. to ABS-14,
Front ABS Sen-
sor.> Rear: <Ref.
to ABS-17, Rear
ABS Sensor.>
No