Subaru 2004 LEGACY, Service Manual

Page: 293 / 609

ABS(diag)-77
ABS (DIAGNOSTICS)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
Step Check Yes No
1 CHECK OUTPUT OF G SENSOR USING
SUBARU SELECT MONITOR.
1) Select {Current Data Display & Save} in
Subaru Select Monitor.
2) Read the G sensor output on Subaru
Select Monitor. Is the reading indicated on dis-
play
−
1.2 — 1.2 m/s when G
sensor is horizontal?
Go to step 2. Go to step 5.
2 CHECK POOR CONTACT IN CONNECTOR. 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 the connectors.
2) Erase the memory.
3) Perform the inspection mode.
4) Read the DTC. Is the same DTC displayed? Replace the
ABSCM only.
<Ref. to ABS-8,
REPLACEMENT,
ABS Control Mod-
ule and Hydraulic
Control Unit
(ABSCM&H/U).> Go to step 4.
4 CHECK ANY OTHER DTC ON DISPLAY. Is any other DTC displayed? Inspect the DTC
using “List of Diag-
nostic Trouble
Code (DTC)”.
<Ref. to
ABS(diag)-39, List
of Diagnostic Trou-
ble Code (DTC).> Temporary poor
contact occurs.
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
connector 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
(B301) No. 21 — No. 10:
Is the resistance 1.8 — 2.4
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
(B301) No. 21 — 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
connector terminals.
Connector & terminal
(B292) No. 2 (+) — No. 3 (
−
):
Is the voltage 2.1 — 2.5 V
when G sensor is on a level? Go to step 9. Replace G sen-
sor. <Ref. to ABS-
18, G Sensor.>