1997 SUBARU LEGACY fuse

H: TROUBLE CODE 31
DIAGNOSIS:
Airbag control module is faulty.
Airbag main harness circuit is open.
Fuse No. 16 is blown.
Body harness circuit is open.
1. Airbag control module inspection
2. Airbag main harness inspection
3. Fuse No. 16 inspection
CAUTION:
Before performing diagnostics on airbag system, turn
ignition switch“OFF”, disconnect battery ground
cable and then wait at least 20 seconds.
After 20 seconds elapse, remove instrument panel
lower cover, and disconnect (AB3) and (AB8), (AB9)
and (AB10).
G5M0559
1. AIRBAG CONTROL MODULE INSPECTION
1) Disconnect connector (AB6) from airbag control module
, and connect it to test harness B2
connector (8B).
2) Connect battery ground cable and turn ignition switch
“ON”(engine off).
3) Measure voltage across connector (5B) terminal and
chassis ground.
: Connector & terminal
(5B) No. 5 (+)—Chassis ground ():
Is voltage more than 10 V?
: Replace airbag control module.
: Go to step2.


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5-5bSUPPLEMENTAL RESTRAINT SYSTEM (ELECTRIC SENSOR TYPE)
5. Diagnostics Chart with Trouble Code

2. AIRBAG MAIN HARNESS INSPECTION
1) Go to step 2) below after performing diagnostics on air-
bag system as per diagnosis procedure under“1. AIRBAG
CONTROL MODULE INSPECTION”previously outlined.
2) Turn ignition switch“OFF”, disconnect battery ground
cable and then wait at least 20 seconds.
B5M0119B
3) Disconnect connector (AB1) from body harness con-
nector (B31) at front lower pillar (driver side), and connect
connector (AB1) to test harness A connector (2A).
4) Measure resistance between test harness A connector
(5A) and test harness B2 connector (5B) terminals.
: Connector & terminal
(5A) No. 9—(5B) No. 5:
Is resistance less than 10Ω?
: Go to step 5).
: Replace airbag main harness.
5) Measure resistance between each terminal of connec-
tors (5A) and (5B) and chassis ground.
: Connector & terminal
(5A) No. 9 (+)—Chassis ground ():
: Go to next.
: Replace airbag main harness.
: Connector & terminal
(5B) No. 5 (+)—Chassis ground ():
Is resistance more than 10 kΩ?
: Go to step3.
: Replace airbag main harness.
G5M0453
3. FUSE No. 16 INSPECTION
Make sure ignition switch is turned“OFF”, then remove and
visually check fuse No. 16.
: Is fuse No. 16 blown?
: Replace fuse No. 16. If fuse No. 16 blows again,
repair body harness.
: Repair body harness.
27
5-5bSUPPLEMENTAL RESTRAINT SYSTEM (ELECTRIC SENSOR TYPE)
5. Diagnostics Chart with Trouble Code

O: AIRBAG WARNING LIGHT REMAINS OFF.
DIAGNOSIS:
Fuse No. 15 is blown.
Body harness circuit is open.
Airbag warning light is faulty.
Airbag main harness is faulty.
Airbag control module is faulty.
1. Fuse No. 15 inspection
2. Body harness inspection
3. Airbag warning light module (in combination
meter) inspection
4. Airbag main harness inspection
CAUTION:
Before performing diagnostics on airbag system, turn
ignition switch“OFF”, disconnect battery ground
terminal, and then wait at least 20 seconds.
G5M0460
1. FUSE No. 15 INSPECTION
Remove and visually check fuse No. 15.
: Is fuse No. 15 blown?
: Replace fuse No. 15.
If fuse No. 15 blows again, go to step2.
: Go to step2.
2. BODY HARNESS INSPECTION
Turn ignition switch“ON”(engine off) to make sure other
warning lights (in combination meter) illuminate.
: Do all the warning lights (in combination
meter) except airbag warning light come
on?
: Go to step3.
: Repair body harness.



36
5-5bSUPPLEMENTAL RESTRAINT SYSTEM (ELECTRIC SENSOR TYPE)
5. Diagnostics Chart with Trouble Code

1. AIRBAG COMPONENT PARTS APPEARANCE
INSPECTION
1) Conduct on-board diagnostic and call up trouble codes
stored in memory.
2) Select trouble code required to check airbag compo-
nent parts from those listed in table and reproduce symp-
tom.
Trouble codes Check parts Refer to 5-5b:
04Airbag module (Passenger)
Airbag main harness
Airbag control moduleW3A2
W4A0
W5A0
11Fuse No. 8
Airbag main harness
Airbag control module
Body harnessT5D3
W4A0
W5A0
—
12Roll connector
Airbag module (Driver)
Airbag main harness
Airbag control moduleW6A0
W3A1
W4A0
W5A0
13Airbag module (Driver)
Roll connector
Airbag main harness
Airbag control moduleW3A1
W6A0
W4A0
W5A0
21Airbag control module W5A0
22Airbag module (Passenger)
Airbag main harness
Airbag control moduleW3A2
W4A0
W5A0
33Airbag control module W5A0
34Airbag main harness
Airbag module (Passenger)
Airbag control moduleW4A0
W3A2
W5A0
41Airbag module (Driver)
Roll connector
Airbag main harness
Airbag control moduleW3A1
W6A0
W4A0
W5A0
42Airbag module (Passenger)
Airbag main harness
Airbag control moduleW3A2
W4A0
W5A0
43Airbag module (Driver)
Roll connector
Airbag main harness
Airbag control moduleW3A1
W6A0
W4A0
W5A0
39
5-5bSUPPLEMENTAL RESTRAINT SYSTEM (ELECTRIC SENSOR TYPE)
5. Diagnostics Chart with Trouble Code

Q: WARNING LIGHT INDICATES TROUBLE
CODE, THEN NORMAL CODE.
—FLASHING NORMAL CODE.—
DIAGNOSIS:
Airbag connector is faulty.
Fuse No. 16 is blown.
Airbag main harness is faulty.
Airbag control module is faulty.
Body harness is faulty.
1. Airbag connector appearance inspection
2. Airbag connector vibration inspection
3. Showering inspection to body
4. Fuse No. 16, airbag main harness, airbag
control module, body harness appearance
inspection
5. Fuse No. 16, airbag main harness, body
harness vibration inspection
6. Showering inspection to body
7. Warning light illumination check
CAUTION:
Before performing diagnostics on airbag system, turn
ignition switch“OFF”, disconnect battery ground
cable, and then wait at least 20 seconds.
1. AIRBAG CONNECTOR APPEARANCE INSPECTION
Conduct appearance inspection on airbag connectors
(AB2) through (AB8).
: Is there anything unusual about the appear-
ance of connectors (AB2) through (AB8)?
: Replace faulty airbag component parts.
: Go to step2.
NOTE:
Check terminals, case and wiring harnesses for damage.






41
5-5bSUPPLEMENTAL RESTRAINT SYSTEM (ELECTRIC SENSOR TYPE)
5. Diagnostics Chart with Trouble Code

2. AIRBAG CONNECTOR VIBRATION INSPECTION
Conduct vibration inspection on airbag connectors (AB2)
through (AB8).
: Do the connectors (AB2) through (AB8) mal-
function again when shaking?
: Replace faulty airbag component parts.
: Go to step3.
NOTE:
Gently shake each airbag connector.
G5M0461
3. SHOWERING INSPECTION TO BODY
Spray water on vehicle body.
CAUTION:
Do not directly spray water on airbag components.
: Does water leak into the passenger com-
partment when showering vehicle?
: Replace faulty airbag component parts.
: Go to step4.
NOTE:
If leaks are noted, also check wiring harnesses as water
may leak along them and wet airbag connectors.
4. FUSE No. 16, AIRBAG MAIN HARNESS, AIRBAG
CONTROL MODULE, BODY HARNESS APPEARANCE
INSPECTION
Conduct appearance inspection on fuse No. 16 5-5b [T5H3].>, airbag main harness [W4A0].>, airbag control module
and body harness.
: Is there anything unusual about the appear-
ance of fuse No. 16, airbag main harness,
airbag control module or body harness?
: Replace faulty airbag component parts.
: Go to step5.
NOTE:
Also check connectors, terminals, wiring harness and case
for damage.
42
5-5bSUPPLEMENTAL RESTRAINT SYSTEM (ELECTRIC SENSOR TYPE)
5. Diagnostics Chart with Trouble Code

5. FUSE No. 16, AIRBAG MAIN HARNESS, BODY
HARNESS VIBRATION INSPECTION
Conduct vibration inspection on fuse No. 16, airbag main
harness and body harness.
CAUTION:
Do not shake or vibrate airbag control module.
: Do fuse No. 16, airbag main harness or body
harness malfunction again when shaking?
: Replace faulty airbag component parts.
: Go to step6.
NOTE:
Gently shake each part.
G5M0461
6. SHOWERING INSPECTION TO BODY
Spray water on vehicle body.
CAUTION:
Do not directly spray water on each part.
: Does water leak into the passenger com-
partment when showering vehicle?
: Replace faulty airbag component parts.
: Go to step7.
NOTE:
If leaks are noted, check wiring harnesses as water may
leak along them and get parts wet.
7. WARNING LIGHT ILLUMINATION CHECK
Turn ignition switch“ON”(engine off) and observe airbag
warning light.
: Does the airbag warning light comes on for
about 7 seconds, then go out and stay out?
: Clear memory.
:Goto“DIAGNOSTICS PROCEDURE”.

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5-5bSUPPLEMENTAL RESTRAINT SYSTEM (ELECTRIC SENSOR TYPE)
5. Diagnostics Chart with Trouble Code

B6M0269A
2. VACUUM HOSE AND PIPE
Check vacuum hose and pipe (which connects actuator
and vacuum pump) for disconnection or cracks.
B6M0270A
3. ACTUATOR
1) Disconnect vacuum hose from actuator.
B6M0174
2) Connect vacuum pump as shown in figure.
3) Make sure that cruise control cable moves smoothly
and quickly when a vacuum pressure of 40.0 kPa (300
mmHg, 11.81 inHg) is applied to actuator.
Stroke: 35 mm (1.38 in)
4) When vacuum pressure is released from condition 3)
above, make sure the cable returns to its original position
smoothly and quickly.
5) After inspection, disconnect vacuum pump and connect
vacuum hose.
4. POWER SUPPLY
1) Measure battery voltage and specific gravity of electro-
lyte.
Standard voltage: 12 V
Specific gravity: Above 1.260
2) Check the condition of the main and other fuses, and
harnesses and connectors. Also check for proper ground-
ing.
3
6-2BODY ELECTRICAL SYSTEM
2. Pre-inspection