Subaru Impreza 2003, Service Manual

Page: 2500 / 3610

ABS-160
ABS (DIAGNOSTICS)
DIAGNOSTICS PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
2 CHECK POOR CONTACT IN CONNECTORS. Is there poor contact in con-
nector between ABSCM&H/U
and G sensor? Repair the con-
nector. Go to step 3.
3 CHECK ABSCM&H/U.
1)Connect all connectors.
2)Erase the memory.
3)Perform the inspection mode.
4)Read out the DTC.
Is the same DTC as in the cur-
rent diagnosis still being out-
put? Replace the
ABSCM&H/U.
<Ref. to ABS-7,
ABS Control Mod-
ule and Hydraulic
Control Unit
(ABSCM&H/U).> Go to step 4.
4 CHECK ANY OTHER DTC APPEARANCE. Are other DTCs being output? Proceed with the
diagnosis corre-
sponding to DTC.
A temporary poor
contact.
5 CHECK INPUT VOLTAGE OF G SENSOR.
1)Turn the ignition switch to OFF.
2)Remove the console box.
3)Remove the G sensor from vehicle. (Do not
disconnect connector.)
4)Turn the ignition switch to ON.
5)Measure the voltage between G sensor con-
nector terminals.
Connector & terminal
(B292) No. 1 (+) — No. 3 (
−−−−
):
Is the voltage 4.75 — 5.25 V? Go to step 6. Repair the har-
ness/connector
between G sensor
and ABSCM&H/U.
6 CHECK OPEN CIRCUIT IN G SENSOR OUT-
PUT HARNESS AND GROUND HARNESS.
1)Turn the ignition switch to OFF.
2)Disconnect the connector from ABSCM&
H/U.
3)Measure the resistance between
ABSCM&H/U connector terminals.
Connector & terminal
LHD: (B301) No. 6 — No. 28:
RHD: (F49) No. 6 — No. 28:
Is the resistance 5.0 — 5.6
k
Ω
?
Go to step 7. Repair the har-
ness/connector
between G sensor
and ABSCM&H/U.
7 CHECK GROUND SHORT IN G SENSOR
OUTPUT HARNESS.
1)Disconnect the connector from G sensor.
2)Measure the resistance between
ABSCM&H/U connector and chassis ground.
Connector & terminal
LHD: (B301) No. 6 — Chassis ground:
RHD: (F49) No. 6 — Chassis ground:
Is the resistance more than 1
M
Ω
?
Go to step 8. Repair the har-
ness between G
sensor and
ABSCM&H/U.
8 CHECK G SENSOR.
1)Connect the connector to G sensor.
2)Connect the connector to ABSCM&H/U.
3)Turn the ignition switch to ON.
4)Measure the voltage between G sensor con-
nector terminals.
Connector & terminal
(B292) No. 2 (+) — No. 3 (
−−−−
):
Is the voltage 2.1 — 2.5 V
when G sensor is in horizontal
position? Go to step 9. Replace the G
sensor. <Ref. to
ABS-21, G Sen-
sor.>
9 CHECK G SENSOR.
Measure the voltage between G sensor con-
nector terminals.
Connector & terminal
(B292) No. 2 (+) — No. 3 (
−−−−
):
Is the voltage 3.7 — 4.1 V
when G sensor is inclined for-
wards to 90
°
?
Go to step 10. Replace the G
sensor. <Ref. to
ABS-21, G Sen-
sor.>
10 CHECK G SENSOR.
Measure the voltage between G sensor con-
nector terminals.
Connector & terminal
(B292) No. 2 (+) — No. 3 (
−−−−
):
Is the voltage 0.5 — 0.9 V
when G sensor is inclined
backwards to 90
°
?
Go to step 11. Replace the G
sensor. <Ref. to
ABS-21, G Sen-
sor.>
Step Check Yes No