Subaru IMPREZA 1995 User manual

FOREWORD
This portion of the service manual has been prepared
to provide SUBARU service personnel with the neces-
sary information and data for the correct maintenance
and repair of SUBARU vehicles.
This manual includes the procedures for maintenance
disassembling, reassembling, inspection and adjust-
ment of components and diagnostics for guidance of
both the fully qualified and the less-experienced
mechanics.
Please peruse and utilize this manual fully to ensure
complete repair work for satisfying our customers by
keeping their vehicle in optimum condition. When
replacement of parts during repair work is needed, be
sure to use SUBARU genuine parts.
All information, illustration and specifications con-
tained in this manual are based on the latest product
information available at the time of publication
approval.
FUJI HEAVY INDUSTRIES LTD.
WIRING DIAGRAM 6-3
1995 IMPREZA SERVICE MANUAL QUICK REFERENCE INDEX
WIRING DIAGRAM SECTION
G176ABE4

Important safety notice
쐌Providing appropriate service and repair is a matter of great importance in the serviceman’s safety maintenance
and safe operation, function and performance which the SUBARU vehicle possesses.
쐌In case the replacement of parts or replenishment of consumables is required, genuine SUBARU parts whose
parts numbers are designated or their equivalents must be utilized.
쐌It must be made well known that the safety of the serviceman and the safe operation of the vehicle would be
jeopardized if he used any service parts, consumables, special tools and work procedure manuals which are
not approved or designated by SUBARU.
All right reserved. This book may not be reproduced
or copied, in whole or in part, without the written
permission of FUJI HEAVY INDUSTRIES LTD.,
TOKYO JAPAN
SUBARU, and are trademarks of
FUJI HEAVY INDUSTRIES LTD.
© Copyright 1994 FUJI HEAVY INDUSTRIES LTD.
2

WIRING DIAGRAM 6-3
Page
D WIRING DIAGRAM ........................................................................................2
1. General Description...................................................................................2
2. Basic Diagnostics Procedures...................................................................8
3. Working Precautions................................................................................11
4. How to Use Wiring Diagram....................................................................14
5. Wiring Diagram........................................................................................16
1. POWER SUPPLY ROUTING ..............................................................16
2. GROUND DISTRIBUTION..................................................................19
3. AIR CONDITIONING SYSTEM...........................................................23
4. ANTI-LOCK BRAKE SYSTEM............................................................27
5. A/T CONTROL SYSTEM.....................................................................29
6. A/T SHIFT LOCK SYSTEM.................................................................33
7. AUDIO SYSTEM .................................................................................34
8. BACK-UP LIGHT SYSTEM.................................................................35
9. CHARGING SYSTEM .........................................................................36
10. COMBINATION METER....................................................................37
11. CRUISE CONTROL SYSTEM...........................................................38
12. DOOR LOCK SYSTEM.....................................................................39
13. ENGINE ELECTRICAL SYSTEM......................................................40
14. FRONT WIPER AND WASHER SYSTEM........................................48
15. FUEL GAUGE SYSTEM ...................................................................49
16. HORN AND CIGARETTE LIGHTER SYSTEM.................................50
17. LIGHTING (HEADLIGHT) SYSTEM..................................................51
18. LIGHTING (TAIL LIGHT⋅ILLUMINATION LIGHT⋅etc.) SYSTEM.......54
19. OIL PRESSURE AND TEMPERATURE GAUGE SYSTEM.............56
20. PARKING BRAKE AND BRAKE FLUID LEVEL
WARNING SYSTEM .........................................................................57
21. POWER WINDOW SYSTEM............................................................58
22. RADIATOR FAN SYSTEM ................................................................60
23. REAR WINDOW DEFOGGER SYSTEM..........................................62
24. REAR WIPER AND WASHER SYSTEM ..........................................63
25. REMOTE CONTROL REARVIEW MIRROR SYSTEM.....................64
26. SEAT BELT WARNING AND KEY WARNING SYSTEM..................65
27. SPOT LIGHT, ROOM LIGHT, FUSE BOX LIGHT, LUGGAGE AND
TRUNK ROOM LIGHT SYSTEM......................................................66
28. SRS (AIRBAG SYSTEM)..................................................................67
29. STARTING SYSTEM.........................................................................68
30. STOP LIGHT SYSTEM .....................................................................69
31. SUNROOF SYSTEM.........................................................................70
32. TURN SIGNAL AND HAZARD SYSTEM..........................................71
33. FRONT FOG LIGHT SYSTEM..........................................................72
6. Electrical Wiring Harness and Ground Point...........................................73

1. General Description
1. HOW TO USE THIS MANUAL
The description of the electrical system is divided into the
charging system, starting system, etc.
1) First, open to the necessary electrical system section
and wiring diagram.
2) Next, open the foldout page of the electrical wiring dia-
gram. By observing the electrical wiring harness’ illustra-
tions (front, instrument panel, etc.), the wiring diagram con-
nector can be located.
G6M0192
G6M0193
2. WIRING DIAGRAM
The wiring diagram of each system is illustrated so that you
can understand the path through which the electric current
flows from the battery.
Sketches and codes are used in the diagrams. They should
read as follows:
1) Each connector and its terminal position are indicated
by a sketch of the connector in a disconnected state which
is viewed from the front, as shown in figure.
2
6-3 WIRING DIAGRAM
1. General Description

2) The number of poles or pins, presence of a lock, and pin
number of each terminal are indicated in the sketch of each
connector.
In the sketch, the highest pole number refers to the num-
ber of poles which the connector has. For example, the
sketch of the connector shown in figure indicates the con-
nector has 9 poles.
Connector used in vehicle Connector shown in wiring diagram
Sketch Symbol Number of poles
G6M0194 G6M0196
G6M0198
Numbered in order from
upper right to lower left.
G6M0195 G6M0197
Numbered in order from
upper left to lower right.
G6M0199
When one set of connectors is viewed from the front side,
the pole numbers of one connector are symmetrical to
those of the other. When these two connectors are con-
nected as a unit, the poles which have the same number
are joined.
3) Electrical wiring harness
The connectors are numbered along with the number of
poles, external colors, and mating connections in the
accompanying list.
3
6-3WIRING DIAGRAM 1. General Description

G6M0200
4) The sketch of each connector in the wiring diagram
usually shows the “A”side of the connector. The relation-
ship between the wire color, terminal number and connec-
tor is described in figure.
NOTE:
A wire which runs in one direction from a connector termi-
nal sometimes may have a different color from that which
runs in the other direction from that terminal.
G6M0216
5) In wiring diagram, connectors which have no terminal
number refer to one-pole types. Sketches of these connec-
tors are omitted intentionally.
G6M0201
6) The following color codes are used to indicate the col-
ors of the wires used.
Color code Color
L Blue
B Black
Y Yellow
G Green
RRed
W White
Br Brown
Lg Light green
Gr Gray
P Pink
Or Orange
Lb Light Blue
V Violet
SA Sealed (Inner)
SB Sealed (Outer)
G6M0202
7) The wire color code, which consists of two letters (or
three letters including Br or Lg), indicates the standard
color (base color of the wire covering) by its first letter and
the stripe marking by its second letter.
4
6-3 WIRING DIAGRAM
1. General Description

8) The table below lists the nominal sectional areas and
allowable currents of the wires.
Nominal
sectional area
mm
2
No. of strands/
strand diameter
Outside
diameter of
finished wiring
mm
Allowable
current
Amps/40°C
0.3 7/0.26 1.8 7
0.5 7/0.32 2.2 (or 2.0) 12
0.75 30/0.18 2.6 (or 2.4) 16
0.85 11/0.32 2.4 (or 2.2) 16
1.25 16/0.32 2.7 (or 2.5) 21
2 26/0.32 3.1 (or 2.9) 28
3 41/0.32 3.8 (or 3.6) 38
5 65/0.32 4.6 (or 4.4) 51
8 50/0.45 5.5 67
CAUTION:
쐌When replacing or repairing a wire, be sure to use
the same size and type of the wire which was originally
used.
NOTE:
쐌The allowable current in the above table indicates the
tolerable amperage of each wire at an ambient tempera-
ture of 40°C (104°F).
쐌The allowable current changes with ambient tempera-
ture. Also, it changes if a bundle of more than two wires is
used.
G6M0203
9) Each unit is directly grounded to the body or indirectly
grounds through a harness ground terminal. Different sym-
bols are used in the wiring diagram to identify the two
grounding systems.
The ground points shown in the wiring diagram refer to the
following:
쎻
GB Body ground
쎻
GE Engine ground
쎻
GR Radio ground
쎻
GD Rear defogger ground
All wiring harnesses are provided with a ground point which
should be securely connected.
5
6-3WIRING DIAGRAM 1. General Description

10) Relays are classified as normally-open or normally-
closed.
The normally-closed relay has one or more contacts.
The wiring diagram shows the relay mode when the ener-
gizing circuit is OFF.
G6M0204
Key to symbols:
쎻→: Current flows.
X→: Current does not flow.
6
6-3 WIRING DIAGRAM
1. General Description

G6M0205
11) Each connector number shown in the wiring diagram
corresponds to that in the wiring harness. The location of
each connector in the actual vehicle is determined by read-
ing the first character of the connector (for example, a “F”
for F8, “i”for i16, etc.) and the type of wiring harness.
The first character of each connector number refers to the
area or system of the vehicle, as indicated in table below.
Symbol Wiring harness and Cord
F Front wiring harness LH & RH
B Bulkhead wiring harness
EEngine wiring harness, Engine module wiring
harness
T Transmission cord
DDoor cord LH & RH, Rear door adapter cord LH &
RH
I Instrument panel wiring harness
R
Rear wiring harness, Rear defogger cord
Room light cord,
Fuel tank cord,
Sunroof cord,
Rear gate cord,
Rear gate lock adapter cord
P Power window main harness
7
6-3WIRING DIAGRAM 1. General Description

2. Basic Diagnostics Procedure
The most important purpose of diagnostics is to determine
which part is malfunctioning quickly, to save time and labor.
A: IDENTIFICATION OF TROUBLE SYMPTOM
Determine what the problem is based on the symptom.
B: PROBABLE CAUSE OF TROUBLE
Look at the wiring diagram and check the system’s circuit.
Then check the switch, relay, fuse, ground, etc.
C: LOCATION AND REPAIR OF TROUBLE
1) Using the diagnostics narrow down the causes.
2) If necessary, use a voltmeter, ohmmeter, etc.
3) Before replacing certain component parts (switch, relay,
etc.), check the power supply, ground, for open wiring
harness, poor connectors, etc. If no problems are
encountered, check the component parts.
D: CONFIRMATION OF SYSTEM OPERATION
After repairing, ensure that the system operates properly.
G6M0206
E: INSPECTION
1. VOLTAGE MEASUREMENT
1) Using a voltmeter, connect the negative lead to a good
ground point or negative battery terminal and the positive
lead to the connector or component terminal.
2) Contact the positive probe of the voltmeter on connec-
tor (A).
The voltmeter will indicate a voltage.
3) Shift the positive probe to connector (B). The voltmeter
will indicate no voltage.
With test set-up held as it is, turn switch ON. The voltme-
ter will indicate a voltage and, at the same time, the light
will come on.
4) The circuit is in good order. If a problem such as a lamp
failing to light occurs, use the procedures outlined above to
track down the malfunction.
8
6-3 WIRING DIAGRAM
2. Basic Diagnostics Procedure

G6M0207
2. CIRCUIT CONTINUITY CHECKS
1) Disconnect the battery terminal or connector so there is
no voltage between the check points.
Contact the two leads of an ohmmeter to each of the check
points.
If the circuit has diodes, reverse the two leads and check
again.
2) Use an ohmmeter to check for diode continuity.
When contacting the negative lead to the diode positive
side and the positive lead to the negative side, there should
be continuity.
When contacting the two leads in reverse, there should be
no continuity.
3) Symbol “o—o”indicates that continuity exists between
two points or terminals. For example, when a switch posi-
tion is “3”, continuity exists among terminals 1, 3 and 6, as
shown in table below.
Terminal 123456
Switch Position
OFF
1쎻쎻
쎻
2쎻쎻쎻
3쎻쎻 쎻
4쎻쎻 쎻
9
6-3WIRING DIAGRAM 2. Basic Diagnostics Procedure

G6M0208
3. HOW TO DETERMINE AN OPEN CIRCUIT
1) Voltmeter Method
An open circuit is determined by measuring the voltage
between respective connectors and ground using a
voltmeter, starting with the connector closest to the power
supply. The power supply must be turned ON so that cur-
rent flows in the circuit. If voltage is not present between a
particular connector and ground, the circuit between that
connector and the previous connector is open.
G6M0209
2) Ohmmeter method
Disconnect all connectors affected, and check continuity in
the wiring between adjacent connectors. When the ohm-
meter indicates “infinite”, the wiring is open.
G6M0210
4. HOW TO DETERMINE A SHORTCIRCUIT
1) Test lamp method
Connect a test lamp (rated at approximately 3 watts) in
place of the blown fuse and allow current to flow through
the circuit. Disconnect one connector at a time from the
circuit, starting with the one located farthest from the power
supply. If the test lamp goes out when a connector is
disconnected, the wiring between that connection and the
next connector (farther from the power supply) is shorted.
G6M0211
2) Ohmmeter method
Disconnect all affected connectors, and check continuity
between each connector and ground. When ohmmeter
indicates continuity between a particular connector and
ground, that connector is shorted.
10
6-3 WIRING DIAGRAM
2. Basic Diagnostics Procedure

3. Working Precautions
1. PRECAUTIONS WHEN WORKING WITH THE
PARTS MOUNTED ON THE VEHICLE
1) When working under a vehicle which is jacked-up,
always be sure to use safety stands.
2) The parking brake must always be applied during work-
ing. Also, in automatic transmission vehicles, keep the
select lever set to the P (Parking) range.
3) Be sure the workshop is properly ventilated when run-
ning the engine. Further, be careful not to touch the belt or
fan while the engine is operating.
4) Be careful not to touch hot metal parts, especially the
radiator and exhaust system immediately after the engine
has been shut off.
2. PRECAUTIONS IN TROUBLE DIAGNOSIS AND
REPAIR OF ELECTRIC PARTS
1) The battery cable must be disconnected from the bat-
tery’s (−) terminal, and the ignition switch must be set to the
OFF position, unless otherwise required by the diagnos-
tics.
2) Securely fasten the wiring harness with clamps and
slips so that the harness does not interfere with the body
end parts or edges and bolts or screws.
3) When installing parts, be careful not to catch them on
the wiring harness.
G6M0212
4) When disconnecting a connector, do not pull the wires,
but pull while holding the connector body.
11
6-3WIRING DIAGRAM 3. Working Precautions

G6M0213
5) Some connectors are provided with a lock. One type of
such a connector is disconnected by pushing the lock, and
the other, by moving the lock up. In either type the lock
shape must be identified before attempting to disconnect
the connector.
To connect, insert the connector until it snaps and confirm
that it is tightly connected.
G6M0214
6) When checking continuity between connector terminals,
or measuring voltage across the terminal and ground,
always contact tester probe(s) on terminals from the wiring
connection side. If the probe is too thick to gain access to
the terminal, use “mini”test leads.
To check water-proof connectors (which are not accessible
from the wiring side), contact test probes on the terminal
side being careful not to bend or damage the terminals.
7) Sensors, relays, electrical unit, etc., are sensitive to
strong impacts.
Handle them with care so that they are not dropped or
mishandled.
12
6-3 WIRING DIAGRAM
3. Working Precautions

ABBREVIATION LIST
Abbr. Full name
A.B.S. Antilock Brake System
ACC Accessory
A/C Air Conditioning
AD Auto Down
AT Automatic Transmission
AU Auto Up
+B Battery
DN Down
DRL Daytime Running Light
E Ground
F/B Fuse & Joint Box
FL1.5 Fusible link 1.5 mm
2
IG Ignition
Illumi. Illumination
Abbr. Full name
LH Left Hand
Lo Low
M Motor
M/B Main Fuse Box
MG Magnet
Mi Middle
MPFI Multi Point Fuel Injection Model
OP Optional Parts
PASS Passing
RH Right Hand
SBF Slow Blow Fuse
ST Starter
SW Switch
UP Up
WASH Washer
13
6-3WIRING DIAGRAM 3. Working Precautions

4. How to Use Wiring Diagram
G6M0215
A: RELAY
A symbol used to indicate a relay.
B: CONNECTOR-1
The sketch of the connector indicates the one-
pole types.
C: WIRING CONNECTION
Some wiring diagrams are indicated in foldouts
for convenience. Wiring destinations are indi-
cated where necessary by corresponding sym-
bols (as when two pages are needed for clear
indication).
D: FUSE NO. & RATING
The “FUSE No. & RATING”corresponds with
that used in the fuse box (main fuse box, fuse
and joint box.)
E: CONNECTOR-2
1. Each connector is indicated by a symbol.
2. Each terminal number is indicated in the cor-
responding wiring diagram in an abbreviated
form.
3. For example, terminal number “C2”refers to
No. 2 terminal of connector (C:F41) shown in
the connector sketch.
14
6-3 WIRING DIAGRAM
4. How to Use Wiring Diagram

F: CONNECTOR SKETCH
1. Each connector sketch clearly identifies the
shape and color of a connector as well as
terminal locations. Non-colored connectors
are indicated in natural color.
2. When more than two types of connector
number are indicated in a connector sketch,
it means that the same type connectors are
used.
G: GROUND
Each grounding point can be located easily by
referring to the corresponding wiring harness.
H: DIODE
A symbol is used to indicate a diode.
I: WIRE TRACING ON EXTENDED
WIRING DIAGRAMS
For a wiring diagram extending over at least two
pages, a symbol (consisting of the same charac-
ters with arrows), as shown below, facilitates
wire tracing from one page to the next.
A)A, B )B
J: SYMBOLS OF WIRE CONNECTION
AND CROSSING
Symbol Refers to wires which are
connected and branched
at the “dot”point.
Symbol Refers to wires which are
crossed but not con-
nected.
K: POWER SUPPLY ROUTING
A symbol is used to indicate the power supply in
each wiring diagram.
“MB-5”,“MB-6”, etc., which are used as power-
supply symbols throughout the text, correspond
with those shown in the POWER SUPPLY
ROUTING in the wiring diagram.
Accordingly, using the POWER SUPPLY ROUT-
ING and wiring diagrams permits service per-
sonnel to understand the entire electrical
arrangement of a system.
SYMBOLS AND ABBREVIATIONS
Anumber of symbols and abbreviations are used
in each wiring diagram to easily identify parts or
circuits.
15
6-3WIRING DIAGRAM 4. How to Use Wiring Diagram

5. Wiring Diagram
1. POWER SUPPLY ROUTING
GU01-02A
16
6-3 WIRING DIAGRAM
5. Wiring Diagram

GU01-02B
17
6-3WIRING DIAGRAM 5. Wiring Diagram

No. LOAD: SYSTEM No.
MB-1 P/W CIRCUIT BREAKER: 21, 31
MB-2 MAIN RELAY: 13
FUEL PUMP RELAY: 13
MB-3 A/C FUSE: 3, 22
MB-4 HEADLIGHT LH: 17
MB-5 DIODE (LIGHTING): 17 LIGHTING SWITCH: 17
DRL CONTROL MODULE: 17
MB-6 HEADLIGHT RH: 17
COMBINATION METER: 17
MB-7
RADIO: 7
SPOT LIGHT: 27
COMBINATION METER: 27
FUSE BOX ILLUMINATION: 27
ROOM LIGHT: 27
LUGGAGE ROOM LIGHT: 27
TRUNK LOOM LIGHT: 27
MB-8 A/C FUSE: 22
SBF-6 HYDRAULIC UNIT: 4
ALT-1 COMBINATION METER: 9, 20
DRL CONTROL MODULE: 17
ST
AT CONTROL MODULE: 5
INHIBITOR SWITCH: 13, 17, 29
ENGINE CONTROL MODULE: 13
STARTER INTERLOCK
RELAY: 17, 29
FB-1 FRONT WASHER MOTOR: 14
FB-2 DIODE (A/C): 22
FB-3 MAIN FAN MOTOR: 22
FB-4
AT CONTROL MODULE: 5
FUEL PUMP RELAY: 13
ENGINE CONTROL MODULE:13
IGNITION COIL: 13
FB-5 HYDRAULIC UNIT: 4
MAIN FAN MOTOR: 22
FB-6 FRONT CLEARANCE LIGHT LH. RH: 18
FB-7 DOOR LOCK TIMER: 12
FB-8 AT SHIFT LOCK CONTROL MODULE: 6
KEY WARNING SWITCH: 6, 26
FB-9 HAZARD SWITCH: 32
FB-10 RADIO: 7
FB-11 CIGARETTE LIGHTER: 16
FB-12 REMOTE CONTROLLED REARVIEW
MIRROR SWITCH: 25
FB-13
AT SHIFT LOCK CONTROL
MODULE: 6
FRONT WIPER MOTOR: 14
FRONT WIPER SWITCH: 14
REAR WASHER MOTOR: 24
REAR WIPER RELAY: 24
REAR WIPER MOTOR: 24
No. LOAD: SYSTEM No.
FB-14 MAIN FAN RELAY 2: 22
FB-15 AT CONTROL MODULE: 5
ENGINE CONTROL MODULE: 13
FB-16 REAR DEFOGGER: 23
FB-17 COMBINATION METER: 23
REAR DEFOGGER SWITCH: 23
FB-18 BACK-UP LIGHT SWITCH: 8
INHIBITOR SWITCH: 8
FB-19 AT SHIFT LOCK CONTROL MODULE: 6
FB-20 HAZARD SWITCH: 32
FB-21
MODE CONTROL PANEL: 3
COMBINATION METER:
4, 5, 9, 13, 15, 19, 20, 26
SEAT BELT TIMER: 26
FB-22 COMBINATION METER: 28
FB-23
FRESH/RECIRC ACTUATOR: 3
EVAPORATION THERMOSWITCH: 3
BLOWER MOTOR RELAY: 3
CHECK CONNECTOR: 4, 5, 11, 13, 28
DRL CONTROL MODULE: 17
DRL RELAY: 17
DRL HI-BEAM RELAY: 17
P/W AND SUNROOF RELAY: 21, 31
FB-24 AIRBAG CONTROL MODULE: 28
FB-25 AIRBAG CONTROL MODULE: 28
FB-26 LIGHTING SWITCH: 18
FB-27 PARKING LIGHT SWITCH: 18
FB-28 PARKING LIGHT SWITCH: 18
FB-29 COMBINATION METER: 5, 18
ILLUMINATION LIGHTS: 18
FB-30 ILLUMINATION CONTROL MODULE: 18
ILLUMINATION LIGHTS: 18
FB-31 STOP LIGHT SWITCH: 5, 6, 11, 30
FB-32 HORN RELAY: 11, 16
FB-33 BLOWER MOTOR RELAY: 3
FB-34 PARKING LIGHT SWITCH: 18
FB-35 REAR COMBINATION LIGHT LH. RH: 18
LICENSE PLATE LIGHT LH. RH: 18
FB-36
A.B.S. G SENSOR: 14
A.B.S. CONTROL MODULE: 4
CRUISE CONTROL MODULE: 11
CRUISE CONTROL MAIN SWITCH: 11
18
6-3 WIRING DIAGRAM
5. Wiring Diagram