BR-39
Brake Vacuum Pump
BRAKE
16.Brake Vacuum Pump
A: REMOVAL
1. BRAKE VACUUM PUMP
1) Disconnect the ground cable from the battery.
2) Disconnect the brake vacuum pump connector.
3) Remove the vacuum hose.
4) Remove the bolt, and remove the brake vacuum
pump.
2. VACUUM HOSE
Remove the clip and remove the vacuum hose.
B: INSTALLATION
1. BRAKE VACUUM PUMP
Install in the reverse order of removal.
Tightening torque:
7.5 N·m (0.76 kgf-m, 5.5 ft-lb)
2. VACUUM HOSE
Install in the reverse order of removal.
CAUTION:
The vacuum hose has an installation direction.
Make sure to install in the proper direction.
C: INSPECTION
1. BRAKE VACUUM PUMP
Inspect for whether or not the pump operates when
battery voltage is applied to the connector terminal.
2. VACUUM HOSE
Check to see that air only flows in one direction,
when air is blown into or sucked from the hose.
(1) To engine
(2) Vacuum hose
(3) Vacuum pipe
(4) Marking (Marking to vacuum pipe side)
BR-00506
BR-00507
(1)
(2)(2)
(4)
(3)
ENG
BVC(diag)-2
Basic Diagnostic Procedure
BRAKE VACUUM CONTROL (BVC) (DIAGNOSTICS)
1. Basic Diagnostic Procedure
A: PROCEDURE
CAUTION:
•Subaru Select Monitor is required for reading DTC, reading the current data and clearing the mem-
ory.
•Remove foreign matter (dust, water, oil, etc.) from the engine control module (ECM) connector
when removing or installing.
NOTE:
•To check the harness for broken wires or short circuits, shake problem spot or connector.
•Refer to “Check List for Interview”.
Step Check Yes No
1CHECK PRE-INSPECTION.
1) Ask the customer when and how the trou-
ble occurred using interview check list.
2) Check the error display. (Odo/trip meter)
Is “Er-bb” displayed on the
screen?
Go to step 3.Go to step 2.
2BASIC INSPECTION
Check the components which might affect the
brake vacuum control.
Is the component that might
affect the vacuum control nor-
mal?
Go to step 3.Repair or replace
each component.
3CHECK INDICATION OF DTC.
1) Turn the ignition switch to OFF.
2) Connect the Subaru Select Monitor to data
link connector.
3) Turn the ignition switch to ON, and the Sub-
aru Select Monitor power switch to ON.
4) Read the DTC.
(DTC).>
5) Record all DTC.
Is DTC displayed? Go to step 5.Go to step 4.
4PERFORM GENERAL DIAGNOSTICS.
Inspect using “General Diagnostic Table”.
Is result of inspection OK? Finish the diagno-
sis.
Go to step 5.
5PERFORM THE DIAGNOSIS.
1) Correct the cause of trouble according to
DTC.
2) Perform the clear memory mode.
Mode.>
3) Perform the inspection mode.
Mode.>
4) Read the DTC.
(DTC).>
Is DTC displayed? Repeat step 4 until
DTC is not shown.
Finish the diagno-
sis.
BVC(diag)-3
Check List for Interview
BRAKE VACUUM CONTROL (BVC) (DIAGNOSTICS)
2. Check List for Interview
A: CHECK
Check the following item about the vehicle’s state.
1. STATUS OF THE ERROR DISPLAY
An error is displayed
in odo/trip meter. Always
Sometimes
Only once
Does not come on
• When/How long does it come on?
Ignition key position LOCK
ACC
ON (before starting engine)
START
ON (after starting engine, while engine is running)
ON (after starting engine, engine is stop)
Timing Immediately after turning the ignition switch to ON
Immediately after turning the ignition switch to START
Accelerating — km/h
— MPH
While traveling at a constant speedkm/h MPH
Reducing speed — km/h
— MPH
BVC(diag)-4
Check List for Interview
BRAKE VACUUM CONTROL (BVC) (DIAGNOSTICS)
2. CONDITIONS UNDER WHICH TROUBLE OCCURS
Environment a) Weather Fine
Cloudy
Rainy
Snowy
Others:
b) Ambient temperature°C (°F)
c) Altitudem (ft)
d) Road Inner city
Suburbs
Highway
General road
Uphill
Downhill
Paved road
Gravel road
Muddy road
Sandy place
Straight road
Sharp cur ve
Gentle curve
S-curve
Road with a slope on both sides
Others:
e) Road surface Dr y
Wet
New-fallen snow
Compressed snow
Frozen slope
Others:
Condition a) Brakes Deceleration: G
continuous / intermittent
b) Accelerator Acceleration: G
continuous / intermittent
c) Vehicle speed km/h MPH
Advancing
Accelerating
Reducing speed
Low speed
Turning
Others:
Immediately after
starting the engine
Idling etc.
BVC(diag)-9
Subaru Select Monitor
BRAKE VACUUM CONTROL (BVC) (DIAGNOSTICS)
6. Subaru Select Monitor
A: OPERATION
1. READ DIAGNOSTIC TROUBLE CODE
(DTC)
1) Prepare the Subaru Select Monitor kit.
TOOL, General Description.>
2) Connect the diagnosis cable to Subaru Select
Monitor.
3) Insert the cartridge to the Subaru Select Monitor.
4) Connect the Subaru Select Monitor to data link
connector.
(1) Data link connector is located in the lower
portion of instrument panel (on the driver’s
side).
(2) Connect the diagnosis cable to data link
connector.
CAUTION:
Do not connect the scan tools except for Suba-
ru Select Monitor.
5) Turn the ignition switch to ON (engine OFF) and
turn the Subaru Select Monitor switch to ON.
6) On the «Main Menu» display screen, select the
{Each System Check} and press the [YES] key.
7) On the «System Selection Menu» display
screen, select the {Brake Negative Pressure Pump
System} and press the [YES] key.
8) Press the [YES] key after the {3.0 DOHC} is dis-
played.
9) On the «Negative Pressure Pump Diagnosis
Menu» display screen, select the {Diagnostic
Code(s) Display} and press the [YES] key.
NOTE:
•For details concerning operation procedure, re-
fer to the “SUBARU SELECT MONITOR OPERA-
TION MANUAL”.
•For details concerning DTCs, refer to “List of Di-
agnostic Trouble Code (DTC)”.
ABS00111
ABS00112
EN-03693
(A) Power switch
(A)
EN-00040
BVC(diag)-10
Subaru Select Monitor
BRAKE VACUUM CONTROL (BVC) (DIAGNOSTICS)
2. READ CURRENT DATA
1) On the «Main Menu» display screen, select the {Each System Check} and press the [YES] key.
2) On the «System Selection Menu» display screen, select the {Brake Negative Pressure Pump System} and
press the [YES] key.
3) Press the [YES] key after the {3.0 DOHC} is displayed.
4) On the «Negative Pressure Diagnosis Menu» display screen, select the {Current Data Display/Save}, and
then press the [YES] key.
5) On the «Data Display Menu» screen, select the {Data Display} and press the [YES] key.
6) Using a scroll key, scroll the display screen up or down until necessary data is shown.
•A list of the support data is shown in the following table.
NOTE:
For details concerning operation procedure, refer to the “SUBARU SELECT MONITOR OPERATION MAN-
UAL”.
3. CLEAR MEMORY MODE
1) On the «Main Menu» display screen, select the
{Each System Check} and press the [YES] key.
2) On the «System Selection Menu» display
screen, select the {Brake Negative Pressure Pump
System} and press the [YES] key.
3) Press the [YES] key after the {3.0 DOHC} is dis-
played.
4) On the «Negative Pressure Pump Diagnosis
Menu» display screen, select the {Clear Memory}
and press the [YES] key.
5) When “Done” and “Turn ignition switch OFF” are
shown on the display screen, turn the Subaru Se-
lect Monitor and ignition switch to OFF.
NOTE:
For details concerning operation procedure, refer
to the “SUBARU SELECT MONITOR OPERATION
MANUAL”.
4. FUNCTION CHECK MODE
1) Connect the test mode connector located under
the glove box.
2) Turn the ignition switch to ON (engine OFF) and
turn the Subaru Select Monitor switch to ON.
3) On the «Main Menu» display screen, select the
{Each System Check} and press the [YES] key.
4) On the «System Selection Menu» display
screen, select the {Brake Negative Pressure Pump
System} and press the [YES] key.
5) Press the [YES] key after the {3.0 DOHC} is dis-
played.
6) On the «Negative Pressure Pump Diagnosis
Menu» display screen, select the {Function Check
Mode} and press the [YES] key.
7) When the “Start Function Check Mode” is shown
on the screen, press the [YES] key.
8) When the “Depress the Brake Pedal 5 Times” is
shown on the screen, depress the brake pedal 5
times, and press the [YES] key while brake pedal is
not depressed.
9) Press the [YES] key after the {OK} is displayed.
Display Contents to be monitored Unit of measure
Atmospheric pressure Atmospheric pressure is displayed. mmHg, kPa or psig
Brake booster pressure Brake booster pressure is displayed. mmHg, kPa or psig
Te s t m o d e t e r m i n a l Te s t m o d e t e r m i n a l c o n n e c t i o n s t a t u s i s d i s p l a y e d . D C h e c k o r U C h e c k
Negative pressure pump motor Negative pressure motor operating status is displayed. ON or OFF
Negative pressure pump motor relay Negative pressure pump motor relay operating status is displayed. ON or OFF
Display Contents to be monitored
Clear Memory? DTC deleting function
(A) Test mode connector
EN-03694
(4)
BVC(diag)-16
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
BRAKE VACUUM CONTROL (BVC) (DIAGNOSTICS)
Step Check Yes No
1CHECK 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.
Te r m i n a l s
No. 1 — No. 3:
No. 2 — No. 3:
Is the resistance 15 kΩ or
less?
Go to step 2.Replace the brake
vacuum sensor.
Sensor.>
2CHECK 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 3.Repair the open
circuit of harness
between ECM and
brake vacuum
sensor connector.
3CHECK 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 4.Repair the ground
short of the har-
ness between
ECM and brake
vacuum sensor
connector.
4CHECK HARNESS BETWEEN ECM AND
BRAKE VACUUM SENSOR CONNECTOR.
Measure the voltage between ECM connector
and chassis 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 5.Repair the battery
short circuit
between ECM and
brake vacuum
sensor connector.
5CHECK 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 6.Replace the ECM.
Engine Control
Module (ECM).>
6CHECK 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).>
BVC(diag)-18
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.
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.
Te r m i n a l s
No. 1 — No. 3:
No. 2 — No. 3:
Is the resistance 15 kΩ or
less?
Go to step 4.Replace the brake
vacuum sensor.
Sensor.>
4CHECK 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 5.Repair the open
circuit of harness
between ECM and
brake vacuum
sensor connector.
5CHECK 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 6.Repair the ground
short circuit
between ECM and
brake vacuum
sensor connector.
6CHECK 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 7.Repair the battery
short of the har-
ness between
ECM and brake
vacuum sensor
connector.
7CHECK 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 8.Replace the ECM.
Engine Control
Module (ECM).>