Contents Wiring diagrams Section: Mechanical - Hydraulic All sections

Brake Vacuum Control (Diagnostics): Other Subaru Forester SJ

Mechanical - Hydraulic 5 illustrations ~272 words

PROCEDURE

CAUTIONSubaru Select Monitor is required for reading DTC, reading the current data and clearing the memory. Remove foreign matter (dust, water, oil, etc.) from the engine control module (ECM) connector when removing or installing.

Note. To check the harness for open or short circuits, shake problem spot or connector. Refer to "Check List for Interview". < Ref. to CHECK LIST FOR INTERVIEW . >

StepCheckYesNo
1 CHECK PRE-INSPECTION. Ask the customer when and how the trouble occurred using the interview check list. < Ref. to CHECK LIST FOR INTERVIEW . > Check the brake vacuum pump warning light.Does the brake vacuum pump warning light illuminate?Go to step 3 .Go to step 2 .
2 BASIC INSPECTION. Check the components which might affect the brake vacuum control. < Ref. to INSPECTION , General Description. >Is the component that might affect the brake vacuum control normal?Go to step 3 .Repair or replace each component.
3 CHECK INDICATION OF DTC. Turn the ignition switch to OFF. Connect the Subaru Select Monitor to data link connector. Turn the ignition switch to ON and run the Subaru Select Monitor. Read the DTC. < Ref. to OPERATION , Read Diagnostic Trouble Code (DTC). > Record all DTC.Is DTC displayed?Record the DTC, time stamp and freeze frame data. Go to step 5 . NOTE: For the time stamp, refer to LAN section. < Ref. to TIME STAMP , CAUTION, General Description. > Depending on DTCs, time stamp may not be stored.Go to step 4 .
4 PERFORM GENERAL DIAGNOSTICS. Perform the inspection by referring to "General Diagnostic Table". < Ref. to INSPECTION , General Diagnostic Table. >Is result of inspection OK?Finish the diagnosis.Go to step 5 .
5 PERFORM DIAGNOSIS. Correct the cause of trouble according to the DTC. < Ref. to LIST , List of Diagnostic Trouble Code (DTC). > Perform the Clear Memory Mode. < Ref. to OPERATION , Clear Memory Mode. > Perform the Inspection Mode. < Ref. to PROCEDURE , Inspection Mode. > Read the DTC. < Ref. to OPERATION , Read Diagnostic Trouble Code (DTC). >Is DTC displayed?Repeat step 5 until DTC is not shown.Finish the diagnosis.
NOTE
For the time stamp, refer to LAN section. < Ref. to TIME STAMP , CAUTION, General Description. > Depending on DTCs, time stamp may not be stored.

CHECK

Check the following items about the vehicle's state.

Scheme 134

Scheme 134: STATE OF BRAKE VACUUM PUMP WARNING LIGHT

Scheme 135

Scheme 135: CONDITIONS UNDER WHICH TROUBLE OCCURS

SRS AIRBAG SYSTEM

The airbag system wiring harness is routed near the main relay and ECM.

CAUTIONDo not use electrical test equipment on wiring harness and connector circuits of the airbag system. Be careful not to damage the airbag system wiring harness.

BATTERY

Measure the battery voltage and check electrolyte.

Standard voltage: 12 V or more

Specific gravity: 1.260 or more

BRAKE VACUUM HOSE

Make sure that the brake vacuum hose is not cracked or loose.

GENERAL TOOL

TOOL NAMEREMARKS
Circuit testerUsed for measuring resistance, voltage and current.
OscilloscopeUsed for measuring the sensor.

Scheme 136

Scheme 136: LOCATION

Scheme 137

Scheme 137

Scheme 138

Scheme 138: ELECTRICAL SPECIFICATION
DescriptionConnector No.Terminal No.Signal (V)Note
Ignition SW ON (engine OFF)Engine ON (idling)
Brake vacuum sensorSignalE158131 - 3.81 - 3.8
Power supplyB1341855
GroundB1341900
Self-shutoff controlB1343800
Brake vacuum pumpRelay driveE1583710 - 13 (When pump is OFF)12 - 14 (When pump is ON)
0 (When pump is ON)0 (When pump is ON)
Electric loadE15810 (When pump is OFF)0 (When pump is OFF)
10 - 13 (When pump is ON)12 - 14 (When pump is ON)

HOW TO USE THE SUBARU SELECT MONITOR

For detailed operation procedures, refer to "PC application help for Subaru Select Monitor".

READ CURRENT DATA

For detailed operation procedures, refer to "PC application help for Subaru Select Monitor".

A list of the support data is shown in the following table.

DisplayContents to be displayedUnit of measure
Atmospheric pressureAtmospheric pressure is displayed.KPa
Brake Booster PressureBrake booster pressure is displayed.KPa

SEQUENCE CONTROL MODE

  1. Turn the ignition switch to ON (engine OFF) and run the Subaru Select Monitor.
  2. On «Main Menu» display, select {Each System Check}.
  3. On «System Selection Menu» display, select {Brake Vacuum Pump System}.
  4. On the «Brake Vacuum Pump System» display, select {Function Check Sequence}.
  5. When «Sequence Control Mode will be started» is shown on the screen, click the [OK] button.
  6. When «Depress Brake Pedal Five Times» is shown on the screen, depress the brake pedal 5 times, and click the [OK] button while the brake pedal is not depressed.
  7. Click the [OK] button after the «OK» is displayed.

Reproduce the malfunction occurrence condition as much as possible.

Drive the vehicle at least ten minutes.

LIST

DTCItemContent of diagnosisReference
11Sensor Output Out of RangeBrake vacuum sensor output error< Ref. to DTC 11 SENSOR OUTPUT OUT OF RANGE , Diagnostic Procedure with Diagnostic Trouble Code (DTC). >
12Compare Error in Other SensorBrake booster relative pressure comparison error< Ref. to DTC 12 COMPARE ERROR IN OTHER SENSOR , Diagnostic Procedure with Diagnostic Trouble Code (DTC). >
13Pressure Sensor Signal FreezeBrake vacuum sensor stuck error< Ref. to DTC 13 PRESSURE SENSOR SIGNAL FREEZE , Diagnostic Procedure with Diagnostic Trouble Code (DTC). >
21Discrepancy in Relays (On)Unmatched drive of brake vacuum pump relay and brake vacuum pump< Ref. to DTC 21 DISCREPANCY IN RELAYS (ON) , Diagnostic Procedure with Diagnostic Trouble Code (DTC). >
22Discrepancy in Relays (Off)Unmatched drive of brake vacuum pump relay and brake vacuum pump< Ref. to DTC 22 DISCREPANCY IN RELAYS (OFF) , Diagnostic Procedure with Diagnostic Trouble Code (DTC). >
23Pump Continuous WorkContinuous drive error of brake vacuum pump< Ref. to DTC 23 PUMP CONTINUOUS WORK , Diagnostic Procedure with Diagnostic Trouble Code (DTC). >