1997 SUBARU LEGACY alarm

B6M0361A
22. Security System
A: REMOVAL AND INSTALLATION
1. STARTER INTERRUPT RELAY
NOTE:
The starter interrupt relay and headlight alarm relay use the
same parts and are mounted parallel to each other.
Therefore, before removal and installation, identify the
starter interrupt relay by the color of its wiring connection.

1) Remove instrument panel lower cover.
2) Disconnect connector of starter interrupt relay.
3) Remove starter interrupt relay.
4) Installation is in the reverse order of removal.
B6M0361A
2. HEADLIGHT ALARM RELAY
NOTE:
The headlight alarm relay and starter interrupt relay use the
same parts and are mounted parallel to each other.
Therefore, before removal and installation, identify the
headlight alarm relay by the color of its wiring connection.

1) Remove instrument panel lower cover.
2) Disconnect connector of headlight alarm relay.
3) Remove headlight alarm relay.
4) Installation is in the reverse order of removal.
B6M0363A
3. ENGINE HOOD SWITCH
1) Disconnect connector of engine hood switch from bot-
tom side of switch body.
2) Remove headlight (LH).
3) Remove attaching bolt, and then remove engine hood
switch.
4) Installation is in the reverse order of removal.
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6-2SERVICE PROCEDURE
22. Security System

B6M0375A
B: INSPECTION
1. STARTER INTERRUPT RELAY
1) Disconnect connector of starter interrupt relay.
2) Connect battery to terminal No.1 and ground terminal
No. 2.
3) Check continuity between terminals as indicated in
table below:
When current flows. Between terminals
No. 3 and No. 5Continuity does not
exist.
When current does not flow. Between terminals
No. 3 and No. 5Continuity exists.
Between terminals
No. 1 and No. 2Continuity exists.
G6M0134
2. HEADLIGHT ALARM RELAY
1) Disconnect connector of headlight alarm relay.
2) Connect battery to terminal No. 1 and ground terminal
No. 2.
3) Check continuity between terminals as indicated in
table below:
When current flows. Between terminals
No. 3 and No. 5Continuity does not
exist.
Between terminals
No. 3 and No. 4Continuity exists.
When current does not flow. Between terminals
No. 3 and No. 5Continuity exists.
Between terminals
No. 3 and No. 4Continuity does not
exist.
Between terminals
No. 1 and No. 2Continuity exists.
B6M0376
3. ENGINE HOOD SWITCH
1) Disconnect connector of engine hood switch.
2) Check continuity between terminals when push rod is
pushed in 1.5 mm (0.059 in) of its stroke.
Terminal
Switch position12
When push rod is
pushed in.
When push rod is
released.
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6-2SERVICE PROCEDURE
22. Security System

6. Security System
A: ELECTRICAL COMPONENTS LOCATION
B6M0403A
1Security control module

2Security indicator light

3RH door key cylinder lock/unlock switch (built-in tamper
switch)

4Door switch

5Door lock/unlock switch

6Trunk lid key cylinder unlock switch (SEDAN) (built-in tamper
switch)

7Trunk lid switch (SEDAN)

8Rear gate key cylinder lock/unlock switch (WAGON)
9Rear gate switch (WAGON)

10LH door key cylinder lock/unlock switch (built-in tamper
switch)

11Starter interrupt relay

12Headlight alarm relay

13Ignition switch (ACC position)

14Engine hood switch

15Horn

16Headlight
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6-2DIAGNOSTICS
6. Security System

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.
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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.














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6-2DIAGNOSTICS
6. Security System

From the previous step. From the previous step.
Indicator light flashes at long intervals (0.2 sec. ON and 2.4 sec.
OFF).
Unlock rear gate using a ignition key and open.
Unlock trunk lid using a ignition key and open.
The alarm system does not operate.
OK Not OKThe alarm system does not operate.OK Not OK
Check trunk unlock switch.
Check trunk unlock switch harness.
Check security control module.
Check rear gate unlock switch.
Check rear gate unlock switch harness.
Check security control module.
Close trunk lid.Close rear gate.
Lock rear gate using a ignition key.
Indicator light illuminates continuously.Indicator light illuminates continuously.
OK Not OK
Check rear gate lock switch.
Check rear gate lock switch harness.
Check security control module.
Wait for 30 seconds.
Indicator light flashes at long intervals (0.2 sec. ON and 2.4 sec.
OFF).
Unlock front RH door using a ignition key and open.
The alarm system does not operate.
OK
 Not OK
Check front RH door key cylinder unlock switch.
Check front RH door key cylinder unlock switch harness.
Check security control module.
Close front RH door and lock using a ignition key.
Indicator light illuminates continuously.
OK
 Not OK
Check front RH door key cylinder lock switch.
Check front RH door key cylinder lock switch harness.
Check security control module.
Finish checking security system.
















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6-2DIAGNOSTICS
6. Security System

L: DIAGNOSTICS PROCEDURE FOR
STARTER INTERRUPT SIGNAL
1. Check starter interrupt output signal for security
control module.
Not OK
OK
5. Check starter interrupt relay.
OK Not OK
Repair or replace
wiring harness of
starter motor circuit.
Replace starter
interrupt relay.
2. Check power supply for starter interrupt relay.
OK
Not OK
Repair or replace wiring harness between starter
interrupt relay and battery.
3. Check continuity of starter interrupt relay.
OK
Not OK
Replace starter interrupt relay.
4. Check harness connector between starter
interrupt relay and security control module.
OK
Not OK
Repair or replace wiring harness between starter
interrupt relay and security control module.
Replace security control module.
B6M0445A
1. CHECK STARTER INTERRUPT OUTPUT SIGNAL
FOR SECURITY CONTROL MODULE.
1) Remove security control module without disconnecting
connector.
2) Measure voltage between security control module con-
nector and body.
Connector & terminal / Specified voltage:
(B93) No. 5—Body / 10 V, or more
3) Set security system in armed state.
4) Open the door without ignition key to operate the secu-
rity system (alarm state).
5) Measure voltage between security control module and
body during alarm state.
Connector & terminal / Specified voltage:
(B93) No. 5—Body/1V,max.





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6-2DIAGNOSTICS
6. Security System

M: DIAGNOSTICS PROCEDURE FOR HORN
ALARM SIGNAL
1. Check horn alarm output signal for security
control module.
Not OK
OK
5. Check horn relay.
OK Not OK
Repair or replace
wiring harness of horn
circuit.
Replace horn relay.
2. Check power supply for horn relay.
OK
Not OK
Repair or replace wiring harness between horn
relay and battery.
3. Check continuity of horn relay.
OK
Not OK
Replace horn relay.
4. Check harness connector between horn relay
and security control module.
OK
Not OK
Repair or replace wiring harness between horn
relay and security control module.
Replace security control module.
B6M0461A
1. CHECK HORN ALARM OUTPUT SIGNAL FOR
SECURITY CONTROL MODULE.
1) Remove security control module without disconnecting
connector.
2) Measure voltage between security control module con-
nector and body.
Connector & terminal / Specified voltage:
(B93) No. 13—Body / 10 V, or more
3) Set security system in armed state.
4) Open the door without ignition key to operate the secu-
rity system (alarm state).
5) Measure voltage between security control module and
body during alarm state.
Connector & terminal / Specified voltage:
(B93) No. 13—Body / repeats 1 V, max. (0.2 sec.)
and 10 V, or more (0.6 sec.)
intervals





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6. Security System