Subaru Legacy IV (2008 year). Manual - part 1111

SL-17

Keyless Entry System

SECURITY AND LOCKS

3. CHECK KEYLESS ENTRY CONTROL MODULE

4. CHECK BODY INTEGRATED UNIT POWER SUPPLY AND GROUND CIRCUIT

Refer to the power supply & ground circuit inspection of the door lock control system. <Ref. to SL-8, CHECK
POWER SUPPLY AND GROUND CIRCUIT, INSPECTION, Door Lock Control System.>

Step

Check

Yes

No

1

CHECK DIAGNOSTIC TROUBLE CODE 
(DTC).
1) Prepare the Subaru Select Monitor kit.
2) Turn the ignition switch to ON (engine OFF) 
and run the “PC application for Subaru Select 
Monitor”.
3) On the «System Selection Menu» display, 
select the {Integ. unit mode}.
4) Select the {Diagnostic Code(s) Display}.
5) Check that the DTC is displayed.

Is DTC B1500 “Keyless UART 
com. Malfunction” displayed?

Go to step 2.

Keyless entry con-
trol module is nor-
mal.

2

CHECK POWER SUPPLY.
1) Disconnect the keyless entry control mod-
ule harness connector.
2) Measure the voltage between harness con-
nector terminal and chassis ground.

Connector & terminal

(i96) No. 4 (+) — Chassis ground (–):

Is the voltage 10 V or more?

Go to step 3.

Check the harness 
for open circuits 
and shorts 
between the key-
less entry control 
module and fuse.

3

CHECK GROUND CIRCUIT.
Measure the resistance between harness con-
nector terminal and chassis ground.

Connector & terminal

(i96) No. 7 — Chassis ground:

Is the resistance less than 10 

:? Go to step 4.

Repair or replace 
the harness.

4

CHECK KEYLESS ENTRY CONTROL MOD-
ULE CIRCUIT.
1) Disconnect the harness connector of body 
integrated unit.
2) Measure the resistance between harness 
connector terminals.

Connector & terminal

(i84) No. 9 — (i96) No. 3:

Is the resistance less than 10 

:? Replace the key-

less entry control 
module. <Ref. to 
SL-54, Keyless 
Entry Control Mod-
ule.>

Repair or replace 
the harness.

SL-18

Keyless Entry System

SECURITY AND LOCKS

5. CHECK DOOR SWITCH

Step

Check

Yes

No

1

CHECK DOOR SWITCH CIRCUIT.
1) Prepare the Subaru Select Monitor kit.
2) Turn the ignition switch to ON (engine OFF) 
and run the “PC application for Subaru Select 
Monitor”.
3) On the «System Selection Menu» display, 
select the {Integ. unit mode}.
4) Select the {Current Data Display}.
5) Read the display of data (driver’s door, pas-
senger’s door, rear right door, rear left door, rear 
gate/trunk SW) when each door is opened/
closed.

Does the display switch 
between OFF 

œ ON when 

each door or rear gate, trunk lid 
is opened/closed?

The door switch 
circuit is OK.

Go to step 2.

2

CHECK HARNESS.
1) Disconnect the harness connector of body 
integrated unit.
2) Disconnect the door switch harness con-
nector that the display does not change.
3) Check the harness for open or short circuits 
between the body integrated unit and the faulty 
door switch.

Connector & terminal

Front door RH:

(i84) No. 32 — (R12) No. 1:

Front door LH:

(i84) No. 19 — (R9) No. 1:

Rear door RH:

(i84) No. 18 — (R16) No. 1:

Rear door LH:

(i84) No. 31 — (R22) No. 1:

Trunk lid switch (Sedan model):

(i84) No. 17 (+) — (R186) No. 3:

Rear gate latch switch (Wagon model):

(i84) No. 17 (+) — (D46) No. 2:

Is harness normal?

Repair or replace 
the harness.

Go to step 3.

3

CHECK HARNESS.
Measure the resistance between faulty door 
switch harness connector and chassis ground.

Connector & terminal

Front door RH:

(R12) No. 3 — Chassis ground:

Front door LH:

(R9) No. 3 — Chassis ground:

Rear door RH:

(R16) No. 3 — Chassis ground:

Rear door LH:

(R22) No. 3 — Chassis ground:

Trunk lid switch (Sedan model):

(R186) No. 1 — Chassis ground:

Rear gate latch switch (Wagon model):

(D46) No. 1 — chassis ground:

Is the resistance less than 10 

:? Go to step 4.

Repair or replace 
the harness.

SL-19

Keyless Entry System

SECURITY AND LOCKS

4

CHECK DOOR SWITCH.
Measure the resistance between faulty door 
switches.

Connector & terminal

(R12) Front RH door switch:
(R9) Front LH door switch:
(R16) Rear RH door switch:
(R22) Rear LH door switch:

No. 1 — No. 3:

Trunk lid switch (Sedan model):

(R186) No. 1 — No. 3:

Rear gate latch switch (Wagon model):

(D46) No. 1 — No. 2:

Is the resistance 1 M

: or more 

when switch is pushed?

Go to step 5.

Replace the faulty 
parts.
• Door switch
• Rear gate latch 
ASSY
• Trunk lid lock 
ASSY

5

CHECK DOOR SWITCH.
Measure the resistance between faulty door 
switches.

Connector & terminal

(R12) Front RH door switch:
(R9) Front LH door switch:
(R16) Rear RH door switch:
(R22) Rear LH door switch:

No. 1 — No. 3:

Trunk lid switch (Sedan model):

(R186) No. 1 — No. 3:

Rear gate latch switch (Wagon model):

(D46) No. 1 — No. 2:

Is the resistance less than 10 

:

when switch is released?

Replace the body 
integrated unit. 
<Ref. to SL-56, 
Body Integrated 
Unit.>

Replace the faulty 
parts.
• Door switch
• Rear gate latch 
ASSY
• Trunk lid lock 
ASSY

Step

Check

Yes

No

SL-20

Keyless Entry System

SECURITY AND LOCKS

6. CHECK KEY WARNING SWITCH

Step

Check

Yes

No

1

CHECK INPUT CIRCUIT.
Check the input signal from the key warning 
switch to the body integrated unit using the Sub-
aru Select Monitor.
1) Prepare the Subaru Select Monitor kit.
2) On the «System Selection Menu» display, 
select the {Integ. unit mode}.
3) Select the {Current Data Display & Save}.
4) Check the input signal to body integrated 
unit by operating the ignition switch.

Does the display switch 
between OFF 

œ ON when the 

key is inserted and removed 
from the ignition switch?

The key warning 
switch is OK.

Go to step 2.

2

CHECK FUSE.
Remove and visually check the fuse No. 14 (in 
the main fuse box).

Is the fuse blown out?

Replace the fuse 
with a new part.

Go to step 3.

3

CHECK KEY WARNING SWITCH INPUT CIR-
CUIT.
1) Disconnect the harness connector of body 
integrated unit.
2) Insert the key into ignition switch. (LOCK 
position)
3) Measure the voltage between harness con-
nector terminal and chassis ground.

Connector & terminal

(B281) No. 7 (+) — Chassis ground (–):

Is the voltage 10 V or more?

Replace the body 
integrated unit. 
<Ref. to SL-56, 
Body Integrated 
Unit.>

Go to step 4.

4

CHECK KEY WARNING SWITCH INPUT CIR-
CUIT.
1) Remove the key from ignition switch.
2) Measure the voltage between harness con-
nector terminal and chassis ground.

Connector & terminal

(B281) No. 7 (+) — Chassis ground (–):

Is the voltage less than 1.5 V?

Replace the body 
integrated unit. 
<Ref. to SL-56, 
Body Integrated 
Unit.>

Go to step 5.

5

CHECK KEY WARNING SWITCH.
1) Disconnect the key warning switch harness 
connector.
2) Insert the key into ignition switch. (LOCK 
position)
3) Measure the resistance between key warn-
ing switch terminals.

Connector & terminal

(B350) No. 3 — No. 4:

Is the resistance less than 10 

:? Go to step 6.

Replace the key 
warning switch.

6

CHECK KEY WARNING SWITCH.
1) Remove the key from ignition switch.
2) Measure the resistance between key warn-
ing switch terminals.

Connector & terminal

(B350) No. 3 — No. 4:

Is the resistance 1 M

: or 

more?

Check the follow-
ing:
• Harness for 
open circuits and 
shorts between the 
key warning switch 
and fuse.
• Harness for 
open or short 
between the body 
integrated unit and 
key warning switch

Replace the key 
warning switch.