BVC(diag)-19
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
BRAKE VACUUM CONTROL (BVC) (DIAGNOSTICS)
8CHECK CURRENT DATA.
1) Turn the ignition switch to ON.
2) Depress the brake pedal several times, until
the pedal becomes firm.
3) Read the current data of the brake negative
pressure pump system using the Subaru
Select Monitor.
Is the atmospheric pressure —
brake booster pressure
between –8 — +8 mmHg?
Te m p o r a r y p o o r
contact occurs.
Replace the ECM.
Engine Control
Module (ECM).>
Step Check Yes No
BVC(diag)-21
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
BRAKE VACUUM CONTROL (BVC) (DIAGNOSTICS)
Step Check Yes No
1CHECK BRAKE VACUUM HOSE.
1) Turn the ignition switch to OFF.
2) Check that status of the brake vacuum
hose connection.
Is the brake vacuum hose con-
nected firmly?
Go to step 2.Connect the brake
vacuum hose.
2CHECK BRAKE VACUUM HOSE.
1) Turn the ignition switch to ON and start
engine.
2) Check for leakage from the brake vacuum
hose.
Is there a leak from the brake
vacuum hose?
Replace the brake
vacuum hose.
Go to step 3.
3CHECK BRAKE VACUUM SENSOR CON-
NECTOR.
Check that status of the brake vacuum sensor
connector connection.
Is the brake vacuum sensor
connector connected firmly?
Go to step 4.Connect the brake
vacuum sensor
connector.
4CHECK BRAKE VACUUM SENSOR.
1) Turn the ignition switch to OFF.
2) Disconnect the brake vacuum sensor con-
nector.
3) Remove the brake vacuum sensor.
4) Measure the resistance between brake
vacuum sensor connector terminals.
Connector & terminal
No. 1 — No. 3:
No. 2 — No. 3:
Is the resistance 15 kΩ or
less?
Go to step 5.Replace the brake
vacuum sensor.
Sensor.>
5CHECK HARNESS BETWEEN ECM AND
BRAKE VACUUM SENSOR CONNECTOR.
1) Disconnect the connectors from ECM.
2) Measure the resistance of the harness
between ECM and the brake vacuum sensor
connector.
Connector & terminal
(B135) No. 30 — (B411) No. 1:
(B135) No. 22 — (B411) No. 3:
(B134) No. 27 — (B411) No. 2:
Is the resistance less than 1
Ω?
Go to step 6.Repair the open
circuit of harness
between ECM and
brake vacuum
sensor connector.
6CHECK HARNESS BETWEEN ECM AND
BRAKE VACUUM SENSOR CONNECTOR.
Measure the resistance of harness between
ECM and chassis ground.
Connector & terminal
(B135) No. 30 — Chassis ground:
(B135) No. 22 — Chassis ground:
(B134) No. 27 — Chassis ground:
Is the resistance more than 1
MΩ?
Go to step 7.Repair the ground
short of the har-
ness between
ECM and brake
vacuum sensor
connector.
7CHECK HARNESS BETWEEN ECM AND
BRAKE VACUUM SENSOR CONNECTOR.
Measure the voltage between ECM and chas-
sis ground.
Connector & terminal
(B135) No. 30 (+) — Chassis ground (–):
(B135) No. 22 (+) — Chassis ground (–):
(B134) No. 27 (+) — Chassis ground (–):
Is the voltage less than 0.5 V? Go to step 8.Repair the battery
short of the har-
ness between
ECM and brake
vacuum sensor
connector.
8CHECK THE BRAKE VACUUM SENSOR
POWER SUPPLY.
1) Connect the connectors to ECM and brake
vacuum sensor.
2) Turn the ignition switch to ON.
3) Measure the voltage between ECM con-
nector terminals.
Connector & terminal
(B135) No. 22 (+) — (B135) No. 30 (–):
Is the voltage 4.75 — 5.25 V? Go to step 9.Replace the ECM.
Engine Control
Module (ECM).>
BVC(diag)-22
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
BRAKE VACUUM CONTROL (BVC) (DIAGNOSTICS)
9CHECK CURRENT DATA.
1) Turn the ignition switch to ON.
2) Depress the brake pedal several times, until
the pedal becomes firm.
3) Read the current data of the brake negative
pressure pump system using the Subaru
Select Monitor.
Is the atmospheric pressure —
brake booster pressure
between –8 — +8 mmHg?
Te m p o r a r y p o o r
contact occurs.
Replace the ECM.
Engine Control
Module (ECM).>
Step Check Yes No
BVC(diag)-25
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
BRAKE VACUUM CONTROL (BVC) (DIAGNOSTICS)
9CHECK BRAKE VACUUM PUMP.
1) Turn the ignition switch to OFF.
2) Remove the brake vacuum pump.
3) Connect the battery positive terminal to the
brake vacuum pump terminal No. 1, and the
negative terminal to terminal No. 2.
Is the brake vacuum pump
operating?
Go to step 10.Replace the brake
vacuum pump.
Pump.>
10 CHECK BRAKE VACUUM PUMP.
1) Connect the brake vacuum pump relay.
2) Connect the connectors to the brake vac-
uum pump and ECM.
3) Turn the ignition switch to ON.
4) Execute the brake negative pressure pump
system function check mode using the Subaru
Select Monitor.
Is the brake vacuum pump
operating?
Te m p o r a r y p o o r
contact occurs.
Replace the ECM.
Engine Control
Module (ECM).>
Step Check Yes No
BVC(diag)-27
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
BRAKE VACUUM CONTROL (BVC) (DIAGNOSTICS)
Step Check Yes No
1CHECK BRAKE VACUUM PUMP RELAY.
1) Turn the ignition switch to OFF.
2) Remove the brake vacuum pump relay from
the relay box.
3) Connect the battery to terminals No. 1 and
No. 3 of the brake vacuum pump relay.
4) Measure the resistance between the brake
vacuum pump relay terminals.
Te r m i n a l s
No. 4 — No. 5:
Is the resistance less than 1
Ω?
Go to step 2.Replace the brake
vacuum pump
relay.
2CHECK BRAKE VACUUM PUMP RELAY
POWER SUPPLY.
1) Turn the ignition switch to ON.
2) Measure the voltage between brake vac-
uum pump relay connector and chassis
ground.
Connector & terminal
(VC2) No. 1 (+) — Chassis ground (–):
(VC2) No. 4 (+) — Chassis ground (–):
Is the voltage more than 10 V? Go to step 3.Repair the open or
ground short cir-
cuit of power sup-
ply circuit.
3CHECK HARNESS BETWEEN ECM AND
BRAKE VACUUM PUMP RELAY CONNEC-
TOR.
1) Turn the ignition switch to OFF.
2) Disconnect the connector of ECM.
3) Measure the resistance of the harness
between ECM and the brake vacuum pump
relay connector.
Connector & terminal
(B136) No. 8 — (VC2) No. 3:
(B135) No. 25 — (VC2) No. 5:
Is the resistance less than 1
Ω?
Go to step 4.Repair the open
circuit of harness
between ECM and
the brake vacuum
pump relay con-
nector.
4CHECK HARNESS BETWEEN THE BRAKE
VACUUM PUMP AND BRAKE VACUUM
PUMP RELAY CONNECTOR.
1) Turn the ignition switch to OFF.
2) Disconnect the brake vacuum pump con-
nector.
3) Measure the resistance of the harness
between the brake vacuum pump and brake
vacuum pump relay connector.
Connector & terminal
(VC2) No. 5 — (B417) No. 1:
Is the resistance less than 1
Ω?
Go to step 5.Repair the open
circuit of the har-
ness between the
brake vacuum
pump and the
brake vacuum
pump relay con-
nector.
5CHECK ECM.
1) Connect the brake vacuum pump relay.
2) Connect the connectors to the brake vac-
uum pump and ECM.
3) Turn the ignition switch to ON.
4) Measure the voltage between ECM and
chassis ground.
Connector & terminal
(B136) No. 8 — Chassis ground (–):
Is the voltage more than 10 V? Replace the ECM.
Engine Control
Module (ECM).>
Te m p o r a r y p o o r
contact occurs.
BVC(diag)-29
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
BRAKE VACUUM CONTROL (BVC) (DIAGNOSTICS)
Step Check Yes No
1CHECK BRAKE VACUUM HOSE.
1) Turn the ignition switch to OFF.
2) Check that status of the brake vacuum
hose connection.
Is the brake vacuum hose con-
nected firmly?
Go to step 2.Connect the brake
vacuum hose.
2CHECK BRAKE VACUUM HOSE.
1) Turn the ignition switch to ON and start
engine.
2) Check for leakage from the brake vacuum
hose.
Is there a leak from the brake
vacuum hose?
Replace the brake
vacuum hose.
Go to step 3.
3CHECK BRAKE VACUUM PUMP RELAY.
1) Turn the ignition switch to OFF.
2) Remove the brake vacuum pump relay from
the relay box.
3) Connect the battery to terminals No. 1 and
No. 3 of the brake vacuum pump relay.
4) Measure the resistance between the brake
vacuum pump relay terminals.
Te r m i n a l s
No. 4 — No. 5:
Is the resistance less than 1
Ω?
Go to step 4.Replace the brake
vacuum pump
relay.
4CHECK BRAKE VACUUM PUMP RELAY
POWER SUPPLY.
1) Turn the ignition switch to ON.
2) Measure the voltage between brake vac-
uum pump relay connector and chassis
ground.
Connector & terminal
(VC2) No. 1 (+) — Chassis ground (–):
(VC2) No. 4 (+) — Chassis ground (–):
Is the voltage more than 10 V? Go to step 5.Repair the open or
ground short cir-
cuit of power sup-
ply circuit.
5CHECK HARNESS BETWEEN ECM AND
BRAKE VACUUM PUMP RELAY CONNEC-
TOR.
1) Turn the ignition switch to OFF.
2) Disconnect the connector of ECM.
3) Measure the resistance of the harness
between ECM and the brake vacuum pump
relay connector.
Connector & terminal
(B136) No. 8 — (VC2) No. 3:
(B135) No. 25 — (VC2) No. 5:
Is the resistance less than 1
Ω?
Go to step 6.Repair the open
circuit of harness
between ECM and
the brake vacuum
pump relay con-
nector.
6CHECK HARNESS BETWEEN THE BRAKE
VACUUM PUMP AND BRAKE VACUUM
PUMP RELAY CONNECTOR.
1) Turn the ignition switch to OFF.
2) Disconnect the brake vacuum pump con-
nector.
3) Measure the resistance of the harness
between the brake vacuum pump and brake
vacuum pump relay connector.
Connector & terminal
(VC2) No. 5 — (B417) No. 1:
Is the resistance less than 1
Ω?
Go to step 7.Repair the open
circuit of the har-
ness between the
brake vacuum
pump and the
brake vacuum
pump relay con-
nector.
7CHECK ECM.
1) Connect the brake vacuum pump relay.
2) Connect the connectors to the brake vac-
uum pump and ECM.
3) Turn the ignition switch to ON.
4) Measure the voltage between ECM and
chassis ground.
Connector & terminal
(B136) No. 8 — Chassis ground (–):
Is the voltage more than 10 V? Replace the ECM.
Engine Control
Module (ECM).>
Te m p o r a r y p o o r
contact occurs.
DI-34
General Diagnostic Table
DIFFERENTIALS
8. General Diagnostic Table
A: INSPECTION
Symptom or trouble Possible cause Remedy
1. Oil leakage(1) Worn, scratched, or incorrectly seated
front or side oil seal. Scored, battered or
excessively wor n sliding surface of com-
panion flange.
Correct or replace.
(2) Clogged or damaged air breather. Clean, repair or replace.
(3) Loose bolts on differential spindle or
side retainer, or incorrectly fitted O-ring.
Tighten the bolts to specified torque.
Replace the O-ring.
(4) Loose rear cover attaching bolts or
damaged gasket.
Tighten the bolts to specified torque.
Replace gasket and apply liquid gasket.
(5) Loose oil filler or drain plug. Retighten and apply liquid gasket.
(6) Wear, damage or incorrect fitting of
spindle, side retainer or oil seal.
Correct or replace.
2. Seizure
NOTE:Seized or damaged parts should be re-
placed, and also other parts should be thor-
oughly checked for any defect and should
be repaired or replaced as required.
(1) Insufficient backlash for hypoid gear. Readjust or replace.
(2) Excessive preload for side, rear or
front bearing.
Readjust or replace.
(3) Insufficient or improper oil used. Replace seized part and fill with speci-
fied oil to specified level.
3. Damage
NOTE:Damaged parts should be replaced, and
also other parts should be thoroughly
checked for any defect and should be re-
paired or replaced as required.
(1) Improper backlash for hypoid gear. Replace.
(2) Insufficient or excessive preload for
side, rear or front bearing.
Readjust or replace.
(3) Excessive backlash for differential
gear.
Replace gear or thrust washer.
(4) Loose bolts and nuts such as hypoid
driven gear bolt
Retighten.
(5) Damage due to overloading. Replace.
4. Noises when starting or shifting
gears
NOTE:
Noises may be caused by differential as-
sembly, universal joint, wheel bearing, etc.
Find out what is actually making noise be-
fore disassembling.
(1) Excessive backlash for hypoid gear. Readjust.
(2) Excessive backlash for differential
gear.
Replace the differential case assembly.
(3) Insufficient preload for front or rear
bearing.
Readjust.
(4) Loose drive pinion nut. Tighten to the specified torque.
(5) Loose bolts and nuts such as side
bearing retainer attaching bolt.
Tighten to the specified torque.
5. Noises when cornering(1) Damaged differential gear. Replace the differential case assembly.
(2) Excessive wear or damage of thrust
washer.
Replace the differential case assembly.
(3) Broken pinion mate shaft. Replace the differential case assembly.
(4) Seized or damaged side bearing. Replace.
6. Gear Noise
NOTE:
Since noises from engine, muffler, trans-
mission, propeller shaft, wheel bearings,
tires, and body are sometimes mistaken for
noises from differential assembly, be care-
ful in checking them. Inspection methods to
locate noises include coasting, accelerat-
ing, cruising, and jacking-up all four wheels.
Perform these inspections according to the
condition of trouble. When listening to nois-
es, shift gears into four wheel drive and
fourth speed position, trying to pick up only
differential noise.
(1) Improper tooth contact of hypoid gear. Readjust or replace hypoid gear set.
(2) Improper backlash of the hypoid gear. Readjust.
(3) Scored or chipped teeth of hypoid
gear.
Replace hypoid gear set.
(4) Seized hypoid gear. Replace hypoid gear set.
(5) Improper preload for front or rear
bearings.
Readjust.
(6) Seized, cut-away or chipped front or
rear bearing.
Replace.
(7) Seized, cut-away or chipped side
bearing.
Replace.
(8) Differential carrier is vibrating. Replace the differential case assembly.
FS-23
Front Crossmember
FRONT SUSPENSION
8. Front Crossmember
A: REMOVAL
1) Lift-up the vehicle, and then remove the front
wheels.
2) Remove the front exhaust pipe.
3) Remove the front crossmember support plate.
4) Remove the front stabilizer.
5) Disconnect the tie-rod end from housing.
6) Remove the front arm.
7) Remove the nuts attaching the engine mount
cushion rubber to crossmember.
8) Remove the steering universal joint.
9) Disconnect the power steering hose from steer-
ing gearbox.
10) Lift the engine approx. 10 mm (0.39 in) using
the chain block.
11) Support the crossmember with a jack, remove
the bolts securing crossmember to body, and then
gradually lower the crossmember with steering
gearbox as a unit.
CAUTION:
When removing the crossmember downward,
be careful that the tie-rod end does not interfere
with drive shaft boot.
B: INSTALLATION
1) Install in the reverse order of removal.
NOTE:
•Use a new bolt and self-locking nut. For parts
which are not reusable, refer to “COMPONENT”.
•Always tighten the stabilizer bushing in the state
where the vehicle is at curb weight and the wheels
are in full contact with the ground.
Tightening torque:
Crossmember to body:
95 N·m (9.7 kgf-m, 70.1 ft-lb)
Engine mounting to Crossmember:
85 N·m (8.7 kgf-m, 62.7 ft-lb)
Front arm to Crossmember:
95 N·m (9.7 kgf-m, 70.1 ft-lb)
Front arm to Support plate:
145 N·m (14.8 kgf-m, 106.9 ft-lb)
Support plate to Body:
150 N·m (15.3 kgf-m, 110.6 ft-lb)
Tie–rod end to housing:
27.0 N·m (2.75 kgf-m, 19.9 ft-lb)
After tightening to the specified torque, tighten the
castle nut further but within 60° until the hole in the
ball stud is aligned with a slot in castle nut
Universal joint:
24 N·m (2.4 kgf-m, 17.4 ft-lb)
Stabilizer clamp
25 N·m (2.5 kgf-m, 18.1 ft-lb)
Stabilizer link:
60 N·m (6.1 kgf-m, 44.3 ft-lb)
Power steering hose to Steering gearbox:
15 N·m (1.5 kgf-m, 11 ft-lb)
2) Purge air from the power steering system.
3) Inspect the wheel alignment and adjust if neces-
sary.
C: INSPECTION
Check the crossmember for wear, damage or
cracks, and then repair or replace if faulty.
FS-00209
FS-00119