1997 SUBARU LEGACY turn signals

C: CONTROL MODULE I/O SIGNAL
B6M0405
Content Terminal No.Measuring conditions and I/O signals
(Ignition switch ACC position)
Door lock/unlock switch1
(INPUT)
Battery voltage is present when all doors and rear gate (WAGON) are locked.

“0”volt is present when one of the doors or rear gate (WAGON) is unlocked.
Key cylinder lock switch2
(INPUT)
“0”volt is present when key cylinder is turned to LOCK position.

Battery voltage is present when key cylinder is in positions other than LOCK.
Tamper switch3
(INPUT)
Battery voltage is present when key cylinder switch is installed to key cylinder.

“0”volt is present when key cylinder switch is removed from key cylinder.
Door switch4
(INPUT)
Battery voltage is present when all doors are closed.

“0”volt is present when one of the doors is open.
Starter interrupt relay5
(OUTPUT)
Battery voltage is present when ignition switch is turned ACC or ON.

“0”volt is present when security system is in alarm state.
Ignition switch (ACC)6
(INPUT)
Battery voltage is present when ignition switch is turned ACC or ON.

“0”volt is present when ignition switch is turned OFF.
Security indicator light7
(OUTPUT)
Battery voltage is present when indicator light goes off.

“0”volt is present when indicator light illuminates.
Power supply (back-up) 8 Battery voltage is constantly present.
Ground 9—
Engine hood switch10
(INPUT)
Battery voltage is present when engine hood is closed.

“0”volt is present when engine hood is open.
Trunk lid switch (SEDAN)
Rear gate switch (WAGON)11
(INPUT)
Battery voltage is present when trunk lid or rear gate is closed.

“0”volt is present when trunk lid or rear gate is open.
Headlight alarm relay12
(OUTPUT)
Battery voltage is present when ignition switch is turned ACC or ON.

“0”volt and battery voltage repeats in alarm state. (Headlights flash intermittently
at 0.2 sec. ON and 0.6 sec. OFF intervals).
Horn relay13
(OUTPUT)
Battery voltage is present when ignition switch is turned ACC or ON.

“0”volt and battery voltage repeats in alarm state. (Horn sounds intermittently at
0.2 sec. ON and 0.6 sec. OFF intervals.)
Key cylinder unlock switch14
(INPUT)
“0”volt is present when key cylinder is turned to UNLOCK position.

Battery voltage is present when key cylinder is in positions other than UNLOCK.
Trunk lid key cylinder unlock
switch (SEDAN)15
(INPUT)
“0”volt is present when trunk lid key cylinder is turned to UNLOCK position.

Battery voltage is present when trunk lid key cylinder is in positions other than
UNLOCK.
89
6-2DIAGNOSTICS
6. Security System

D: BASIC DIAGNOSTICS PROCEDURE
Start security system check.
Fully open all door windows and turn ignition switch OFF.
Take key out of ignition, exit vehicle and lock driver’s door.
Indicator light illuminates.
OK The light flashes.
 The light does not
illuminate.
Check indicator harness.
Check security indicator light.
Check driver’s door key cylinder lock/unlock switch.
Check security control module.
Check whether switch input signal remains UNLOCK.
Check wiring harness.
Check switch input signals.
(Harnesses and switches separately)
(Tamper, door, hood, trunk and rear gate
switch)Check security control module.
Wait for 30 seconds.
Indicator light flashes at long intervals (0.2 sec. ON and 2.4 sec.
OFF).
OK
 Not OK
Check security control module.
Unlock driver’s door using the inside lock knob and open door.
The horn sounds and headlights flash intermittently at 0.2 sec. ON
and 0.6 sec. OFF intervals.
The engine will not start even if the ignition switch is turned to
START. Indicator lamp goes out.
OK Starter motor runs.
 All are not OK.
Check driver’s door switch.
Check wiring harness.
Check security control module.
 Horn is not OK.
Check horn
operation by
pushing horn pad
on steering wheel.
OK
 Not OK
Check horn.
Check horn relay.
Check security control module.
Check harness between horn relay and security control module.
 Headlights are not
OK.
Check headlights
operation by
turning light switch
ON/OFF.
OK
 Not OK
Check headlight
bulbs.
Check combination
switch.
Check headlight
relay.
Check starter interrupt relay.
Check wiring harness.
Check security control module.Check headlight alarm relay.
Check security control module.
Check wiring harness.
The alarm system continues to operate for 150 seconds.
OK Not OK
The horn and
headlights turn off.
The starter motor
does not run.
OK
 Not OK
Check security
control module.
Unlock the driver’s door using ignition key.
Continues to next step.














90
6-2DIAGNOSTICS
6. Security System

10N1CHECK FOR OTHER CAUSES AFFECT-
ING EXHAUST GAS.
: Is CO % more than 2 % after engine warm-
up?
: Check fuel system.
NOTE:

Check for use of improper fuel.

Check if engine oil or coolant level is extremely low.
: Go to step10N2.
OBD0145A
10N2
CHECK FRONT OXYGEN SENSOR DATA.
1) Turn ignition switch to OFF.
2) Connect the Subaru Select Monitor or the OBD-II gen-
eral scan tool to data link connector.
3) Start engine and Turn the Subaru Select Monitor and
the OBD-II general scan tool switch to ON.
4) Warm-up the engine until coolant temperature is above
70°C (160°F) and keep the engine speed at 2,000 rpm to
3,000 rpm for one minute.
B2M0487
5) Read data on Subaru Select Monitor or the OBD-II gen-
eral scan tool.

Subaru Select Monitor
Designate mode using function key.
Function mode: F12

F12: Front oxygen sensor max. and min. output signals
are indicated at the same time.
: Is the difference of voltage less than 0.1 V
between the value of max. output and min.
output with function mode F12?
: Go to step10N3.
: Replace front oxygen sensor.

OBD-II general scan tool
For detailed operation procedures, refer to the OBD-II Gen-
eral Scan Tool Instruction Manual.
173
2-7ON-BOARD DIAGNOSTICS II SYSTEM
10. Diagnostic Chart with Trouble Code for LHD Vehicles

5. Control Module I/O Signal
G6M0015
ContentTerminal
No.Measuring conditions and I/O signals (ignition switch ON and engine idling)
Main power supply 2
Battery 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 9
Battery voltage is present when switch is turned ON.

“0”volt is present when switch is turned OFF.
SET/COAST switch 10
Battery voltage is present when switch is turned ON.

“0”volt is present when switch is turned OFF.
Ignition switch 12
Battery 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 15
Battery 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

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
1. CHECK THE SIGNAL USING A SELECT MONITOR.
1) Turn ignition switch to ON.
2) Turn cruise control main switch to ON.
3) Set select monitor in“FA 0”mode.
4) Check signals for proper operation.
(1) When pushing the SET switch:
LED No. 1 goes out—lights.
(2) When pushing the RESUME switch:
LED No. 2 goes out—lights.
B6M0533
B6M0527
2. CHECK THE CRUISE CONTROL COMMAND
SWITCH.
1) Disconnect connector from command switch.
2) Measure voltage between connector (S1) and body.
Connector & terminal / Specified voltage:
(S1) No. 1—Body / 10 V, or more
3) Check for harness short circuit between command
switch and body.
Terminals / Specified resistance:
No. 2—Body / 1 MΩ, min.
No. 3—Body / 1 MΩ, min.
B6M0534
4) Measure resistance between each terminal of switch
side connector to check the switch operation.
Terminals:
No. 1—No. 2 (SET/COAST SWITCH)
No. 1—No. 3 (RESUME/ACCEL SWITCH)
Specified resistance:
10Ω, max. (ON)
1MΩ, min. (OFF)
18
6-2BODY ELECTRICAL SYSTEM
8. Diagnostics Chart with Trouble Code

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
1. CHECK THE SIGNAL USING A SELECT MONITOR.
1) Turn ignition switch to ON.
2) Turn cruise control main switch to ON.
3) Apply parking brake securely.
4) Set select monitor in“FA 0”mode.
5) Release the clutch pedal. (MT model)
6) Depress the brake pedal and check signals for proper
operation.
Stop light switch: LED No. 3 goes out—lights.
Brake switch : LED No. 4 goes out—lights.
7) Release the brake pedal.
8) Depress the clutch pedal and check signal for proper
operation. (MT model)
Clutch switch: LED No. 4 goes out—lights.
9) Set the selector lever from D to N position and check
signal for proper operation. (AT model)
Inhibitor switch: LED No. 5 goes out—lights.
G6M0183
2. CHECK BRAKE SWITCH AND STOP LIGHT
SWITCH.
1) Remove connector of stop and brake switch.
2) Check circuit between each terminal.
Pedal operationBrake switch between
No. 1—No. 4Stop light switch between
No. 2—No. 3
Depressing the
brake pedal.1MΩ,ormore 1Ω, or less
Without
depressing the
brake pedal.1Ω, or less 1 MΩ,ormore
G6M0184
3. CHECK CLUTCH SWITCH. (MT MODEL)
1) Disconnect connector from clutch switch.
2) Check continuity of the clutch switch.
Terminals / Specified resistance:
No. 1—No. 2 / 10Ω, max. (Without pedal
depressing.)
/1MΩ, min. (Pedal depressing.)
20
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
28
6-2BODY ELECTRICAL SYSTEM
8. Diagnostics Chart with Trouble Code

G3M0151
3) Turn ignition switch and select monitor switch ON.
4) After display is shown, press slash“/”key.
5) After AT mode is displayed, press function“[0]”.
(Display returns to AT mode when slash“/”is pressed during
on-board diagnostic operation.)
G3M0152
4. READ TROUBLE CODE SHOWN ON DISPLAY.
1) Connect select monitor.
2) Designate mode using function key.
Press [F] [B] [0] [ENT] in that order.
3) Ensure trouble code(s) is shown.
G3M0152
5. PREVIOUS TROUBLE CODE READING
1) Connect select monitor.
2) Designate mode using function key.
Press [F] [B] [1] [ENT] in that order.
3) Ensure displayed trouble code(s).
C: USING AN OSCILLOSCOPE
A malfunction can be determined by displaying the waveforms
of input/output signals on the oscilloscope.
1. DIAGNOSIS
A simple comparison of the waveforms may lead to an incor-
rect diagnosis. To exactly determine the sources of the mal-
function it will be necessary to determine them under consid-
eration about information other than waveforms.
2. APPLYING INPUT/OUTPUT SIGNALS
Connect the probe directly with the terminal of the signal.
11
[T4C2] FOREWORDFOREWORD
4. Diagnosis and Checking Procedure Using Instruments