SUBARU LEGACY 1997 Service Repair Manual

B6M0248B
5) Measure resistance of harness connector between
cruise control module and body to make sure that circuit
does not short.
Connector & terminal / Specified resistance:
(B94) No. 19—Body / 1 MΩ, min.
B3M0289
4. CHECK VEHICLE SPEED SENSOR 2.
1) Disconnect connector from vehicle speed sensor 2.
2) Measure resistance between terminals of vehicle speed
sensor 2.
Terminals / Specified resistance:
No. 1—No. 2 / 350—450Ω
B3M0256
WARNING:
Be careful not to be caught up by the running wheels.
3) Set the vehicle on free roller, or lift-up the vehicle and
support with safety stands.
4) Drive the vehicle at speed greater than 20 km/h (12
MPH).
5) Measure voltage between terminals of vehicle speed
sensor 2.
Terminals / Specified voltage:
No. 1—No. 2 / 2 V, or more (AC range)
B3M0257

Using an oscilloscope:
(1) Turn ignition switch to OFF.
(2) Set oscilloscope to vehicle speed sensor 2.
(3) Drive the vehicle at speed greater than 20 km/h (12
MPH).
(4) Measure signal voltage.
Specified voltage (V): 5 V, min.
B3M0254A
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6-2BODY ELECTRICAL SYSTEM
8. Diagnostics Chart with Trouble Code

B6M0196
E: TROUBLE CODE 14 AND 22
—SET/COAST SWITCH, RESUME/ACCEL
SWITCH, CANCEL SWITCH—
DIAGNOSIS:

Short circuit inside the SET SW and RESUME SW.
TROUBLE SYMPTOM:

Cruise control cannot be set. (Cancelled immediately.)
1. Check short circuit of cruise control
command switch.
OK
Not OK
Replace the command switch.
Check for short circuit in harness between command
switch and cruise control module.
B6M0535

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6-2BODY ELECTRICAL SYSTEM
8. Diagnostics Chart with Trouble Code

B6M0536
1. CHECK SHORT CIRCUIT OF CRUISE CONTROL
COMMAND SWITCH.
1) Turn ignition switch to ON.
2) Measure voltage between each terminal of connector
(S1).
Terminals / Specified resistance:
SET switch ON
(S1) No. 1—(S1) No.2/10—13 V
RESUME switch ON
(S1) No. 1—(S1) No.3/10—13 V
CANCEL switch ON
(S1) No. 1—(S1) No.2/10—13 V
(S1) No. 1—(S1) No.3/10—13 V
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6-2BODY ELECTRICAL SYSTEM
8. Diagnostics Chart with Trouble Code

B6M0198
F: TROUBLE CODE 23 AND 24
—CRUISE CONTROL MODULE BUILT-IN
RELAY, CPU RAM—
DIAGNOSIS:

Welding of built-in relay of cruise control module.

Failure of built-in CPU RAM of cruise control module.
TROUBLE SYMPTOM:

Cruise control is cancelled and memorized cruise speed
is also cancelled.

Once cruise control is cancelled, cruise control cannot
be set until the ignition switch and cruise main switch turns
OFF, and then turns ON again.
NOTE:
Perform real-time diagnosis (“FA 0”mode) and check
vehicle speed signal with select monitor.
When input signals are in good condition, failure is in cruise
control module.
(Check power supply and ground condition of cruise con-
trol module.)
B6M0291
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6-2BODY ELECTRICAL SYSTEM
8. Diagnostics Chart with Trouble Code

B6M0200
G: TROUBLE CODE 31, 32 AND 33
—VACUUM PUMP, AIR VALVE, RELEASE
VA LV E—
DIAGNOSIS:

Open or poor contact of vacuum pump motor, air valve
and release valve.
TROUBLE SYMPTOM:

Cruise control cannot be set. (Cancelled immediately.)
1. Measure resistance of vacuum pump motor,
air valve and release valve.
OK
Not OK
Malfunction in vacuum pump motor, air valve and
release valve.
2. Perform a circuit test in harness between
cruise control module and vacuum pump
motor, air valve, release valve.
OK
Not OK
Repair or replace wiring harness.
Failure of the cruise control module.
(Check input and output voltage.)
B6M0292


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6-2BODY ELECTRICAL SYSTEM
8. Diagnostics Chart with Trouble Code

B6M0271
1. MEASURE RESISTANCE OF VACUUM PUMP
MOTOR, AIR VALVE AND RELEASE VALVE.
1) Disconnect connector of vacuum pump and valve.
2) Measure resistance of vacuum pump motor, air valve
and release valve.
Terminals / Specified resistance:
No. 2—No. 3 / 46Ω(Vacuum pump motor)
No. 2—No. 1 / 69Ω(Air valve)
No. 2—No. 4 / 69Ω(Release valve)
B6M0293A
2. PERFORM A CIRCUIT TEST IN HARNESS
BETWEEN CRUISE CONTROL MODULE AND
VACUUM PUMP MOTOR, AIR VALVE, RELEASE
VA LV E .
1) Disconnect connectors from cruise control module,
vacuum pump and valve.
2) Measure resistance of harness connector between
cruise control module, vacuum pump motor, air valve and
release valve.
Connector & terminal / Specified resistance:
(B7) No. 1—(B94) No. 5 / 10Ω, max.
(B7) No. 2—(B94) No. 14 / 10Ω, max.
(B7) No. 3—(B94) No. 7 / 10Ω, max.
(B7) No. 4—(B94) No. 13 / 10Ω, max.
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6-2BODY ELECTRICAL SYSTEM
8. Diagnostics Chart with Trouble Code

9. Diagnostics Chart with Select
Monitor
A: FUNCTION MODE
Applicable cartridge of select monitor: No. 498349601
Function mode Contents Abbreviation Unit of measure Page
F00 ROM ID number YEAR—33
F01 Vehicle speed signal VSP MPH 33
F02 Vehicle speed signal VSP km/h 33
F03 Memorized cruise set speed MSP MPH 34
F04 Memorized cruise set speed MSP km/h 34
FA 0 O N)OFF signal——35
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6-2BODY ELECTRICAL SYSTEM
9. Diagnostics Chart with Select Monitor

B6M0243
B: MODE F00
—ROM ID NUMBER (YEAR)—
CONDITION:
Ignition switch“ON”
SPECIFIED DATA:
Presentation display

Probable cause (Item outside“specified data”)
1. Error 1
Check for loose or disconnected connector, and
discontinued circuit, etc.
2. Error 2Check for poor contact of cartridge, or different type
cartridge.
G6M0174
C: MODE F01 AND F02
—VEHICLE SPEED SIGNAL (VSP)—
CONDITION:
Driving at constant speed.
SPECIFIED DATA:
Compare speedometer with monitor indications.

F01: Vehicle speed is indicated in mile per hour (MPH).

F02: Vehicle speed is indicated in kilometer per hour
(km/h).

Probable cause (Item outside“specified data”)
1. Vehicle speed sensor 2
Check vehicle speed sensor line.
<Ref. to 6-2 [T8D0].>
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6-2BODY ELECTRICAL SYSTEM
9. Diagnostics Chart with Select Monitor

B6M0205
D: MODE F03 AND F04
—MEMORIZED CRUISE SET SPEED (MSP)—
CONDITION:
Driving at minimum of 40 km/h (25 MPH) and set cruise
control.
SPECIFIED DATA:
Compare displayed vehicle speed on select monitor in
mode“F03”and“F04”with the speed in mode“F01”and
“F02”.

F03: Memorized cruise set speed is indicated in mile
per hour (MPH).

F04: Memorized cruise set speed is indicated in kilome-
ter per hour (km/h).
NOTE:

F01: Actual vehicle speed is indicated in mile per hour
(MPH).

F02: Actual vehicle speed is indicated in kilometer per
hour (km/h).

Probable cause (Item outside“specified data”)
1. Cruise control module
Check cruise control module input/output signals.
2. Cruise control command switchCheck cruise control command switch.
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6-2BODY ELECTRICAL SYSTEM
9. Diagnostics Chart with Select Monitor

LED No. Signal name Display
1 SET/COAST switch SE
2 RESUME/ACCEL switch RE
3 Stop light switch ST
4
Brake switch

Clutch switch (MT)BR
5 Inhibitor switch (AT) N
6——
7——
8——
9——
10——
SE RE ST BR N
—————
1
2345
678910
E: MODE FA0
—ON↔OFF SIGNAL—
Requirement for LED“ON”.
LED No. 1 SET/COAST switch is turned to ON.
LED No. 2 RESUME/ACCEL switch is turned to ON.
LED No. 3 Stop light switch is turned to ON.
(Brake pedal is depressed.)
LED No. 4
Brake switch is turned to ON.

Clutch switch is turned to ON. (MT model)
(Clutch pedal is depressed.)
LED No. 5 Select lever is set to“P”or“N”position. (AT
model)
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6-2BODY ELECTRICAL SYSTEM
9. Diagnostics Chart with Select Monitor