Page 1857 of 2248

B6M0271
5. VACUUM PUMP AND VALVE
1) Measure resistance of vacuum pump and valve.
(1) Disconnect connector from vacuum pump and valve.
(2) Measure resistance between each terminal of
vacuum pump and valve.
Terminals / Specified resistance:
No. 2—No. 3 / 100Ωor less (Vacuum pump
motor)
No. 2—No. 1 / 69Ω(Air valve)
No. 2—No. 4 / 69Ω(Release valve)
B6M0272
2) Check for leakage and sticking of vacuum valve.
(1) Disconnect connector from vacuum pump and valve.
(2) Make sure that cruise control cable moves smoothly
when connecting + (positive) battery cable to terminal
No. 2 and (negative) battery cable to terminals No. 1,
3 and 4 of vacuum pump and valve connector.
Stroke: 35 mm (1.38 in)
Movement time: Within 3 seconds
(3) When the battery cable is disconnected from condi-
tion (2) above, make sure the cable returns to its origi-
nal position smoothly.
Movement time: Within 1.5 seconds
(4) Connect battery to each terminal and check cable
movement.
Terminal No. Battery
Cruise control
cable operation
1234
———————
Pull
Hold
Release
4
6-2BODY ELECTRICAL SYSTEM
2. Pre-inspection
Page 1858 of 2248
3. Electrical Components Location
B6M0273A
1Actuator
2Vacuum pump and valve
3Inhibitor switch (AT)
4Cruise control main switch
5Cruise control command switch
6Cruise control module
7Stop and brake switch
8Clutch switch (MT)
5
6-2BODY ELECTRICAL SYSTEM
3. Electrical Components Location
Page 1859 of 2248
4. Schematic
B6M0274
6
6-2BODY ELECTRICAL SYSTEM
4. Schematic
Page 1860 of 2248

5. Control Module I/O Signal
G6M0015
ContentTerminal
No.Measuring conditions and I/O signals (ignition switch ON and engine idling)
Main power supply 2Battery voltage is present when main power is turned ON.
“0”volt is present when main power is turned OFF.
Inhibitor switch (AT) (U.S.A.)
N position switch (AT) (CANADA)4“0”volt is present when selector lever is set to P or N position (CANADA: N position only).
Battery voltage is present when selector lever is other than P or N position (CANADA: N
position only).
Air valve 5“0”volt is present when vehicle is stopped.
ON-and-OFF (“0”-and-battery voltage) operation is alternately repeated while cruise control
is operating.
GND 6—
Vacuum pump motor 7“0”volt is present when vehicle is stopped.
ON-and-OFF (“0”-and-battery voltage) operation is alternately repeated while cruise control
is operating.
Data link connector 8—
RESUME/ACCEL switch 9Battery voltage is present when switch is turned ON.
“0”volt is present when switch is turned OFF.
SET/COAST switch 10Battery voltage is present when switch is turned ON.
“0”volt is present when switch is turned OFF.
Ignition switch 12Battery voltage is present when ignition switch is turned ON.
“0”volt is present when ignition switch is turned OFF.
Release valve 13“0”volt is present when vehicle is stopped.
ON-and-OFF (“0”-and-battery voltage) operation is alternately repeated while cruise control
is operating.
Power supply to vacuum pump
motor, air valve, release valve14“0”volt is present when vehicle is stopped.
Battery voltage is present while cruise control is operating.
Cruise main switch 15Battery voltage is present during pressing the main switch, and then approx. 12 V is
present while switch is turned ON.
“0”volt is present when switch is turned OFF.
Brake switch 16Turn the cruise main switch to ON and leave clutch pedal released (MT).
Then check that;
“0”volt is present when brake pedal is depressed.
Battery voltage is present when brake pedal is released.
Additionally only in MT vehicle, keep the cruise main switch to ON and leave brake pedal
released.
Then check that;
“0”volt is present when clutch pedal is depressed.
Battery voltage is present when clutch pedal is released.
Data link connector 17—
Data link connector 18—
Vehicle speed sensor 2 19Lift-up the vehicle until all four wheels are raised off ground, and then rotate any wheel manu-
ally.
Approx. 5 and 0 volt pulse signals are alternately input to cruise control module.
Stop light switch 20Turn ignition switch to OFF.
Then check that;
Battery voltage is present when brake pedal is depressed.
“0”volt is present when brake pedal is released.
NOTE:
Voltage at terminals 5, 7, 13 and 14 cannot be checked unless vehicle is driving by cruise control operation.
7
6-2BODY ELECTRICAL SYSTEM
5. Control Module I/O Signal
Page 1861 of 2248
![SUBARU LEGACY 1995 Service Repair Manual 6. Diagnostics Chart for On-board
Diagnosis System
A: BASIC DIAGNOSTICS PROCEDURE
Trouble occurs.
Pre-inspection <Ref. to 6-2 [T200].>
Check if cruise control main switch turns ON prop-
erly.
OK
Not SUBARU LEGACY 1995 Service Repair Manual 6. Diagnostics Chart for On-board
Diagnosis System
A: BASIC DIAGNOSTICS PROCEDURE
Trouble occurs.
Pre-inspection <Ref. to 6-2 [T200].>
Check if cruise control main switch turns ON prop-
erly.
OK
Not](/manual-img/17/57432/w960_57432-1860.png)
6. Diagnostics Chart for On-board
Diagnosis System
A: BASIC DIAGNOSTICS PROCEDURE
Trouble occurs.
Pre-inspection
Check if cruise control main switch turns ON prop-
erly.
OK
Not OK
Diagnostics Chart for Power Line
[T700].>
(Main switch fails when turning to ON.)
Check if cruise speed is properly set while driving at
minimum of 40 km/h (25 MPH).
OK
Not OK
Diagnostics Chart with Trouble Code
[T800].> (When cruise control cannot be set.)
Check if cruise control is properly released during
operation.
OK
Not OK
Check if cruise speed is held within set speed ±3
km/h (±2 MPH).
OK
Not OK
Basic inspection of actuator, vacuum pump and
valve (When is not running
at a fixed speed.)
Check if RESUME/ACCEL switch functions properly.
OK
Not OK
Diagnostics Chart with Trouble Code
[T800].> (When cruise control cannot be set.)
Check if SET/COAST switch functions properly.
OK
Not OK
Check if CANCEL switch functions properly. (Airbag
equipped model)
OK
Not OK
Check if cruise speed is released when brake pedal
is depressed.
OK
Not OK
Set cruise speed again. Check if cruise speed is
released when clutch pedal is depressed (MT
model) or when select lever is moved to“Neutral.”
OK
Not OK
Cruise control system is in good order.
8
6-2BODY ELECTRICAL SYSTEM
6. Diagnostics Chart for On-board Diagnosis System
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B: ON-BOARD DIAGNOSIS WITH SELECT
MONITOR
1. GENERAL
The on-board diagnosis function of the cruise control sys-
tem uses an external select monitor.
The on-board diagnosis function operates in two
categories, which are used depending on the type of prob-
lems;
Cruise cancel conditions diagnosis
Real-time diagnosis
Applicable cartridge No.: 498349601
Cruise cancel conditions diagnosis
This category of diagnosis requires actual vehicle driv-
ing in order to determine the cause, (as when cruise
speed is cancelled during driving although cruise cancel
condition is not entered).
Cruise control module memory stores the cancel condi-
tion (Code No.) which occurred during driving. When
there are plural cancel conditions (Code No.), they are
shown in order, for 2 seconds per Code No., on the
select monitor.
CAUTION:
The cruise control memory stores not only the
cruise“cancel”which occurred (although“cancel”
operation is not entered by the driver), but also the
“cancel”condition input by the driver.
The content of memory is cleared when ignition
switch or cruise main switch is turned OFF.
Real-time diagnosis
The real-time diagnosis function is used to determine
whether or not the input of output signal system is in good
order, according to signal emitted from switches, sensors,
etc.
Vehicle cannot be driven at cruise speed because prob-
lems occurs in the cruise control system or its associ-
ated circuits.
Monitor the signal conditions from switches and sen-
sors.
9
6-2BODY ELECTRICAL SYSTEM
6. Diagnostics Chart for On-board Diagnosis System
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2. CRUISE CANCEL CONDITIONS DIAGNOSIS
1) Connect select monitor.
2) Start the engine and turn cruise control main switch to
ON.
3) Set select monitor in“FB0”mode.
4) Drive vehicle at least 40 km/h (25 MPH) with cruise
speed set.
5) If cruise speed is canceled itself (without doing any
cancel operations), a trouble code will appear on select
monitor display.
CAUTION:
A trouble code will also appear when cruise cancel
is effected by driver. Do not confuse.
Have a co-worker ride in vehicle to assist in diagno-
sis during driving.
NOTE:
Trouble code will be cleared by turning ignition switch or
cruise control main switch to OFF.
3. REAL-TIME DIAGNOSIS
1) Connect select monitor.
2) Turn ignition switch and cruise control main switch to
ON.
3) Set select monitor in“FA 0”mode.
4) Ensure that normal indication is displayed when con-
trols are operated as indicated below:
When SET/COAST switch is pressed.
When RESUME/ACCEL switch is pressed.
When brake pedal is depressed. (Stop and brake switch
turns ON.)
When clutch pedal is depressed. (MT model)
When select lever is set to N position. (AT model)
10
6-2BODY ELECTRICAL SYSTEM
6. Diagnostics Chart for On-board Diagnosis System
Page 1864 of 2248
7. Diagnostics Chart for Power Line
A: BASIC DIAGNOSTICS PROCEDURE
Drive at cruise speed.
Cruise speed can be set.
(Cruise control is available.)Cruise speed cannot be set.
(Cruise control is not available.)
Check cruise control main switch
light and circuit.
Check cruise control main
switch circuit.
OK
Not OK
Repair.
Check cruise control main
switch.
OK
Not OK
Repair.
Faulty cruise control module.
11
6-2BODY ELECTRICAL SYSTEM
7. Diagnostics Chart for Power Line