1996 SUBARU LEGACY Ecu

H: DIAGNOSTICS PROCEDURE FOR ENGINE
HOOD SWITCH SIGNAL
1. Check engine hood switch input signal for
security control module.
Not OK
OK
Go to next step on basic diagnostics procedure.

2. Check engine hood switch.
OK
Not OK
Replace engine hood switch.
Repair or replace wiring harness between engine
hood switch and security control module.
B6M0451A
1. CHECK ENGINE HOOD SWITCH INPUT SIGNAL
FOR SECURITY CONTROL MODULE.
1) Remove security control module without disconnecting
connector.
2) Turn engine hood switch ON/OFF and measure voltage
between security control module connector and body.
Connector & terminal / Specified voltage:
(B93) No. 10—Body / 10 V, or more (Hood
closed)
/ 1 V, max. (Hood opened)
2. CHECK ENGINE HOOD SWITCH.
Refer to 6-2 [W22B3] for inspection of engine hood switch.


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6. Security System

I: DIAGNOSTICS PROCEDURE FOR TRUNK
LID SWITCH (SEDAN) OR REAR GATE
SWITCH (WAGON) SIGNAL
1. Check trunk lid switch (SEDAN) or rear gate
switch (WAGON) input signal for security
control module.
Not OK
OK
Go to next step on basic diagnostics procedure.

2. Check trunk lid switch (SEDAN) or rear gate
switch (WAGON).
OK
Not OK
Replace trunk lid switch (or rear gate switch).
Repair or replace wiring harness between trunk lid
switch (or rear gate switch) and security control
module.
B6M0450A
1. CHECK TRUNK LID SWITCH (SEDAN) OR REAR
GATE SWITCH (WAGON) INPUT SIGNAL FOR
SECURITY CONTROL MODULE.
1) Remove security control module without disconnecting
connector.
2) Turn trunk lid switch (or rear gate switch) ON/OFF and
measure voltage between security control module connec-
tor and body.
Connector & terminal / Specified voltage:
(B93) No. 11—Body / 10 V, or more
(Lid or gate closed)
/ 1 V, max.
(Lid or gate opened)
2. CHECK TRUNK LID SWITCH (SEDAN) OR REAR
GATE SWITCH (WAGON).
Refer to 6-2 [W8B2], [W8B3] for inspection of trunk lid
switch/rear gate switch.
NOTE:
The trunk lid switch/rear gate switch is used for both trunk
room light/luggage room light.


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6. Security System

J: DIAGNOSTICS PROCEDURE FOR DOOR
LOCK/UNLOCK SWITCH SIGNAL
1. Check door lock/unlock switch input signal
for security control module.
Not OK
OK
Go to next step on basic diagnostics procedure.

2. Check door lock/unlock switch.
OK
Not OK
Replace door lock/unlock switch.
Repair or replace wiring harness between door lock/
unlock switch and security control module.
B6M0407A
1. CHECK DOOR LOCK/UNLOCK SWITCH INPUT
SIGNAL FOR SECURITY CONTROL MODULE.
1) Remove security control module without disconnecting
connector.
2) Close all the doors and rear gate (WAGON), and lock
with ignition key.
3) Measure voltage between security control module con-
nector and body.
Connector & terminal / Specified voltage:
(B93) No. 1—Body / 10 V, or more
NOTE:
When one of the door (driver, passenger or rear gate) lock
knobs is in unlocked position, the voltage may be 1 V, max.
4) Unlock the door with ignition key.
5) Measure voltage between security control module con-
nector and body.
Connector & terminal / Specified voltage:
(B93) No. 1—Body/1V,max.
2. CHECK DOOR LOCK/UNLOCK SWITCH.
Refer to 6-2 [W22B5] for inspection of door lock/unlock
switch.


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6. Security System

K: DIAGNOSTICS PROCEDURE FOR KEY
CYLINDER LOCK/UNLOCK SWITCH AND
TAMPER SWITCH SIGNAL
NOTE:
Key cylinder lock switch, key cylinder unlock switch and
tamper switch are combined as a unit.
1. Check key cylinder switch input signal for
security control module.
Not OK
OK
Go to next step on basic diagnostics procedure.

2. Check key cylinder switch.
OK
Not OK
Replace key cylinder switch.
Repair or replace wiring harness between key
cylinder switch and security control module.
B6M0499A
1. CHECK KEY CYLINDER SWITCH INPUT SIGNAL
FOR SECURITY CONTROL MODULE.
1) Remove security control module without disconnecting
connector.
2) Measure voltage between security control module con-
nector and body while turning each key cylinder with igni-
tion key.
Doors (RH and LH), and rear gate (WAGON)
Connector & terminal / Specified voltage:
(B93) No. 2—Body/1V,max. (LOCK position)
/ 10 V, or more (other than
LOCK position)
B6M0447A
(B93) No. 14—Body/1V,max. (UNLOCK position)
/ 10 V, or more (other than
UNLOCK position)


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6. Security System

B6M0446A
Trunk lid (SEDAN)
Connector & terminal / Specified voltage:
(B93) No. 15—Body/1V,max.
(UNLOCK position)
/ 10 V, or more (other than
UNLOCK position)
B6M0409A
3) Measure voltage between security control module con-
nector and body while removing/installing key cylinder
switch from/to door outer handle.
Connector & terminal / Specified voltage:
(B93) No. 3—Body / 10 V, or more
(Switch is installed.)
/ 1 V, max.
(Switch is removed.)
NOTE:
For SEDAN vehicles, remove key cylinder switch from
trunk lid key cylinder to perform the above inspection.
2. CHECK KEY CYLINDER SWITCH.
Refer to 6-2 [W22B4] for inspection of key cylinder lock/
unlock switch and tamper switch.
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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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B6M0506A
2. CHECK POWER SUPPLY FOR STARTER
INTERRUPT RELAY.
1) Remove starter interrupt relay without disconnecting
connector.
2) Measure voltage between starter interrupt relay con-
nector and body.
Connector & terminal / Specified voltage:
(B59) No. 1—Body / 10 V, or more
B6M0455
3. CHECK CONTINUITY OF STARTER INTERRUPT
RELAY.
1) Remove starter interrupt relay.
2) Check continuity between terminals No. 1 and No. 2 of
starter interrupt relay.
B6M0500A
4. CHECK HARNESS CONNECTOR BETWEEN
STARTER INTERRUPT RELAY AND SECURITY
CONTROL MODULE.
1) Disconnect connectors of starter interrupt relay and
security control module.
2) Measure resistance of harness connector between
starter interrupt relay and security control module.
Connector & terminal / Specified resistance:
(B59) No. 2—(B93) No.5/10Ω, max.
5. CHECK STARTER INTERRUPT RELAY.
Refer to 6-2 [W22B1] for inspection of starter interrupt
relay.
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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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