cruise control SUBARU FORESTER 1999 Service Repair Manual

3. Cruise Control System
A: PRECAUTION
1. SUPPLEMENTAL RESTRAINT SYSTEM
ªAIRBAGº
Airbag system wiring harness is routed near the
cruise control module and cruise control command
switch.
CAUTION:
IAll airbag system wiring harness and con-
nectors are yellow. Do not use electrical test
equipment on these circuits.
IBe careful not to damage airbag system wir-
ing harness when servicing the cruise control
module and cruise control command switch.
B: PRE-INSPECTION
1. FUNCTION TESTS
Conduct road tests by selecting a smooth, flat road
or use free rollers for road test simulation.
ICruise Control Main Switch
1) Turn ignition switch to ON.
2) Check that cruise control main switch indicator
light comes on when main switch is pressed (ON).
3) Check that main switch indicator light goes out
when main switch is pressed again (OFF).
4) Turn ignition switch to OFF with main switch ON
(indicated by illumination). Turn ignition switch ON
again to ensure that main switch indicator light
remains OFF.
ICruise Control Command Switch
1) Check that cruise control command switch is
properly set in ªSET/COASTº, ªRESUME/ACCELº,
or ªCANCELº mode.
2) Also check that command switch returns to the
original position when released.
IConstant Speed Test
1) Turn cruise control main switch to ON.
2) Drive the vehicle at a speed greater than 40
km/h (25 MPH).
3) Press command switch to set in ªSET/COASTº
mode.
4) Ensure that vehicle is maintained at the speed
set when command switch was pressed.
IAcceleration Test
1) Set vehicle speed at a speed greater that 40
km/h (25 MPH).
2) Ensure that vehicle continues to accelerate
while holding command switch in ªRESUME/
ACCELº mode, and that vehicle maintains that
optional speed when command switch is released.
IDeceleration Test
1) Set vehicle speed at an optional speed greater
than 40 km/h (25 MPH).
2) Ensure that vehicle continues to decelerate
while holding command switch in ªSET/COASTº
mode, and that it maintains that optional speed
when command switch is released.
NOTE:
When vehicle speed reaches the lower speed limit
of 30 km/h (19 MPH) during deceleration, cruise
control will be released.
2. CRUISE CONTROL CABLE
3B21 : CHECK CRUISE CONTROL CABLE.
Check accelerator cable (A) and cruise control
cable (B) installation.
S6M0099B
:Is the cruise control cable securely
installed to the left of the accelerator
cable?
: Go to step3B22.
: Install cruise control cable securely. Go
to step3B22.
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[T3B2]6-2DIAGNOSTICS
3. Cruise Control System

3B22 : CHECK ACCELERATOR CABLE.
Check function of accelerator cable (A) and cruise
control cable (B).
S6M0099B
:Does the accelerator cable throttle
cam move when the cruise control
throttle is moved by hand?
: Repair accelerator cable throttle cam.
Go to step3B23.
: Go to step3B23.
3B23 : CHECK THROTTLE CAM.
Check function of throttle cam.
:Does the throttle cam move
smoothly?
: Go to step3B24.
: Repair throttle cam. Go to step3B24.3B24 : CHECK CABLE FREE PLAY.
Ensure that throttle cam-to-lever clearance is
within specifications.
B6M0241A
:Is throttle cam-to-lever clearance
between 0 and 1 mm (0 and 0.04 in)?
: Go to step3B31.
: Adjust cable end by adjusting nuts. Go
to step3B31.
NOTE:
Ensure that cap is positioned in groove.
3. VACUUM HOSE
3B31 : CHECK VACUUM HOSE VISUALLY.
Check vacuum hose (A) (which connects actuator
(B) and intake manifold).
S6M0216B
:Is there disconnection or cracks in
vacuum hose?
: Replace vacuum hose. Go to step
3B41.
: Go to step3B41.
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6-2[T3B2]DIAGNOSTICS
3. Cruise Control System

4. ACTUATOR
3B41 : CHECK FUNCTION OF ACTUATOR.
1) Disconnect vacuum hose (A) from actuator (B).
S6M0216B
2) Connect vacuum pump as shown in figure.
S6M0218
3) Make sure that cruise control cable moves
smoothly and quickly when a vacuum pressure of
40.0 kPa (300 mmHg, 11.81 inHg) is applied to
actuator.
:Does cruise control cable have a
stroke of 35 mm (1.38 in)?
: Go to step3B42.
: Replace actuator. [W12B1].> Go to step3B42.
NOTE:
IWhen vacuum pressure is released from condi-
tion 3) above, make sure the cable returns to its
original position smoothly and quickly.
IAfter inspection, disconnect vacuum pump and
connect vacuum hose.3B42 : MEASURE RESISTANCE OF VALVE.
1) Disconnect connector from actuator.
2) Measure resistance between terminals of
actuator.
Terminals
No. 2 Ð No. 3:
S6M0219
:Is resistance less than 100W?
: Go to step3B43.
: Replace actuator. [W12B1].>
3B43 : MEASURE RESISTANCE OF VALVE.
Measure resistance between terminals of actuator.
Terminals
No. 2 Ð No. 1:
S6M0219
:Is resistance less than 69W?
: Go to step3B44.
: Replace actuator. [W12B1].>
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[T3B4]6-2DIAGNOSTICS
3. Cruise Control System

3B44 : MEASURE RESISTANCE OF VALVE.
Measure resistance between terminals of actuator.
Terminals
No. 2 Ð No. 4:
S6M0219
:Is resistance less than 69W?
: Go to step3B45.
: Replace actuator. [W12B1].>
3B45 : CHECK FOR LEAKAGE AND STICK-
ING OF VALVES.
1) Disconnect connector from actuator.
2) Make sure that cruise control cable moves
smoothly when connecting + (positive) battery
cable to terminal No. 2 and þ (negative) battery
cable to terminals No. 1, 3 and 4 of actuator con-
nector.
S6M0220
:Does cruise control cable have a
stroke of 35 mm (1.38 in) within 3 sec-
onds?
: Go to step3B46.
: Replace actuator. [W12B1].> Go to step3B46.3B46 : CHECK FOR LEAKAGE AND STICK-
ING OF VALVES.
When the battery cable is disconnected from
former condition Step 2),
make sure the cable returns to its original position
smoothly.
:Does cruise control cable get back to
its original position within 1.5 sec-
onds?
: Go to step3B47.
: Replace actuator. [W12B1].> Go to step3B47.
3B47 : CHECK CABLE MOVEMENT.
Connect + (positive) battery cable to terminal No.
2 and þ (negative) battery cable to terminals No. 1,
3 and 4 of actuator connector.
S6M0220
:Does cruise control perform pull
operation?
: Go to step3B48.
: Replace actuator. [W12B1].> Go to step3B48.
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6-2[T3B4]DIAGNOSTICS
3. Cruise Control System

3B48 : CHECK CABLE MOVEMENT.
Connect + (positive) battery cable to terminal No.
2 and þ (negative) battery cable to terminals No. 1
and 4 of actuator connector.
S6M0220
:Does cruise control perform hold
operation?
: Go to step3B49.
: Replace actuator. [W12B1].> Go to step3B49.
3B49 : CHECK CABLE MOVEMENT.
Connect + (positive) battery cable to terminal No.
2 and þ (negative) battery cable to terminal No. 4
of actuator connector.
S6M0220
:Does cruise control perform release
operation?
: Go to step3B51.
: Replace actuator. [W12B1].> Go to step3B51.
5. POWER SUPPLY
3B51 : CHECK BATTERY.
Measure battery specific gravity of electrolyte.
:Is battery specific gravity more than
1.250?
: Go to step3B52.
: Charge or replace battery. [W2A0].> Go to step3B52.
3B52 : CHECK FUSES, CONNECTORS AND
HARNESSES.
Check the condition of the main and other fuses,
and harnesses and connectors. Also check for
proper grounding.
:Is there anything unusual about the
appearance of main fuse, fuse,
harness, connector and grounding?
: Repair or replace faulty parts. End of
pre-inspection.
: End of pre-inspection.
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[T3B5]6-2DIAGNOSTICS
3. Cruise Control System

C: ELECTRICAL COMPONENTS LOCATION
S6M0106A
(1) Actuator (with valves)
(2) Inhibitor switch (AT)
(3) Cruise control main switch(4) Cruise control command switch
(5) Cruise control module
(6) Stop and brake switch(7) Clutch switch (MT)
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6-2[T3C0]DIAGNOSTICS
3. Cruise Control System

D: SCHEMATIC
S6M0390
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[T3D0]6-2DIAGNOSTICS
3. Cruise Control System

E: CONTROL MODULE I/O SIGNAL
G6M0015
Content Terminal No. Measuring conditions and I/O signals (ignition switch ON and engine idling)
Vent valve 1IPower supply is ON when vehicle is stopped.
ION-and-OFF (ª0º-and-battery voltage) operation is alternately repeated while
cruise control is operating.
Safety valve 2IPower supply is ON when vehicle is stopped.
ION-and-OFF (ª0º-and-battery voltage) operation is alternately repeated while
cruise control is operating.
Ignition switch 3IBattery voltage is present when ignition switch is turned ON.
Iª0º volt is present when ignition switch is turned OFF.
Cruise control main switch 4IBattery voltage is present when main power is turned ON.
Iª0º volt is present when main power is turned OFF.
Power supply to vacuum valve,
vent valve, safety valve and
indicator light5IBattery voltage is present when main power is turned ON.
Iª0º volt is present when main power is turned OFF.
SET/COAST switch 6IBattery voltage is present when command switch is turned to SET/COAST
position.
Iª0º volt is present when command switch is released.
RESUME/ACCEL switch 7IBattery voltage is present when command switch is turned to RESUME/
ACCEL position.
Iª0º volt is present when command switch is released.
Brake switch 8 Set select lever to any position other than ªPº or ªNº position (AT) / leave
clutch pedal released (MT), while cruise control main switch is turned ON.
Then check that;
IBattery voltage is present when brake pedal is released.
Iª0º volt is present when brake pedal is depressed, or
IBattery voltage is present when clutch pedal is released (MT).
Iª0º volt is present when clutch pedal is depressed (MT).
IBattery voltage is present when select lever is in any position other than ªPº
or ªNº position (AT).
Iª0º volt is present when select lever is set to ªPº or ªNº position (AT).
Clutch switch (MT)/
Inhibitor switch (AT)9IBattery voltage is present when clutch pedal is released (MT).
Iª0º volt is present when clutch pedal is depressed (MT).
IBattery voltage is present when select lever is in any position other than ªPº
or ªNº position (AT).
Iª0º volt is present when select lever is set to ªPº or ªNº position (AT).
Vacuum valve 11IPower supply is ON when vehicle is stopped.
ION-and-OFF (ª0º-and-battery voltage) operation is alternately repeated while
cruise control is operating.
Set signal to transmission con-
trol module (AT)12ITCM emits a ground-level signal while driving vehicle at least 40 km/h (25
MPH) with SET switch ON.
Ground 13 Ð
Check connector/
OBD-II service connector14 Ð
Check connector/
OBD-II service connector15 Ð
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6-2[T3E0]DIAGNOSTICS
3. Cruise Control System

Content Terminal No. Measuring conditions and I/O signals (ignition switch ON and engine idling)
Vehicle speed sensor (MT)
Automatic transmission control
module (AT)18 Lift-up the vehicle until all four wheels are raised off ground, and then rotate
any wheel manually. Approx. 5 and 0 volt pulse signals are alternately input to
cruise control module.
Stop light switch 19 Turn ignition switch to OFF. Then check that;
IBattery voltage is present when brake pedal is depressed.
Iª0º volt is present when brake pedal is released.
Ground 20 Ð
NOTE:
Voltage at terminals 1, 2, 11 and 12 cannot be checked unless vehicle is driving by cruise control operation.
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[T3E0]6-2DIAGNOSTICS
3. Cruise Control System

F: DIAGNOSTICS CHART FOR ON-
BOARD DIAGNOSIS SYSTEM
1. BASIC DIAGNOSTIC PROCEDURE
3F11 : CHECK CRUISE CONTROL MAIN
SWITCH.
1) Trouble occurs.
2) Perform pre-inspection.
3) Check cruise control main switch.
:Does cruise control main switch turn
ON?
: Go to step3F12.
: Go to ªDiagnostics Chart for Power
Lineº.
3F12 : CHECK CRUISE SPEED IS SET.
:Does cruise speed properly set while
driving at minimum of 40 km/h (25
MPH)?
: Go to step3F13.
: Go to ªDiagnostics Chart with Trouble
Codeº.
3F13 : CHECK CRUISE CONTROL IS
RELEASED.
:Does cruise control properly release
during operation?
: Go to step3F14.
: Go to ªDiagnostics Chart with Trouble
Codeº.
3F14 : CHECK CRUISE SPEED IS HELD
WITHIN SET SPEED.
:Does cruise speed hold within set
speed
±3 km/h (2 MPH)?
: Go to step3F15.
: Go to pre-inspection of actuator. to 6-2 [T3B4].>
3F15 : CHECK RESUME/ACCEL SWITCH.
:Does RESUME/ACCEL switch func-
tion properly?
: Go to step3F16.
: Go to ªDiagnostics Chart with Trouble
Codeº. 3F16 : CHECK SET/COAST SWITCH.
:Does SET/COAST switch function
properly?
: Go to step3F17.
: Go to ªDiagnostics Chart with Trouble
Codeº.
3F17 : CHECK CANCEL SWITCH.
:Does CANCEL switch function prop-
erly?
: Go to step3F18.
: Go to ªDiagnostics Chart with Trouble
Codeº.
3F18 : CHECK CRUISE SPEED IS
RELEASED.
:Does cruise speed release when
brake pedal is depressed?
: Go to step3F19.
: Go to ªDiagnostics Chart with Trouble
Codeº.
3F19 : CHECK CRUISE SPEED IS
RELEASED.
:Does cruise speed release when
clutch pedal is depressed?
: Cruise control system is in correct order.
: Go to ªDiagnostics Chart with Trouble
Codeº.
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6-2[T3F1]DIAGNOSTICS
3. Cruise Control System