1995 SUBARU LEGACY Control unit

B: LIST OF OUTPUT MODES
1. FUNCTION MODE
Mode Contents Abbr. Unit Contents of display Page
F00 Mode display——AT or EGI mode (when monitor is connected.) 61
F01 Battery voltage VB V Battery voltage applied to control unit. 61
F02 Vehicle speed sensor 1 VSP1 m/h Vehicle speed (miles/h) sent from vehicle speed sensor 1. 62
F03 Vehicle speed sensor 1 VSP1 km/h Vehicle speed (km/h) sent from vehicle speed sensor 1. 62
F04 Vehicle speed sensor 2 VSP2 m/h Vehicle speed (miles/h) sent from vehicle speed sensor 2. 62
F05 Vehicle speed sensor 2 VSP2 km/h Vehicle speed (km/h) sent from vehicle speed sensor 2. 62
F06 Engine speed EREV rpm Engine speed sent from ECM. 63
F07 ATF temperature sensor ATFT°F ATF temperature (°F) sent from ATF temperature sensor. 63
F08 ATF temperature sensor ATFT°C ATF temperature (°C) sent from ATF temperature sensor. 63
F09 Throttle position sensor THV V Voltage sent from throttle position sensor. 64
F10 Gear position GEAR—Transmission gear position 64
F11 Line pressure duty PLDTY % Duty ratio flowing through duty solenoid A. 65
F12 Lock-up duty LUDTY % Duty ratio flowing through duty solenoid B. 66
F13 AWD duty 4WDTY % Duty ratio flowing through duty solenoid C. 67
F14Throttle position sensor
power supplyTHVCC V Power supply voltage to throttle position sensor 68
F15 Mass air flow signal AFM V Output voltage from air flow sensor 68
56
3-2AUTOMATIC TRANSMISSION AND DIFFERENTIAL
8. Diagnostic Chart with Select Monitor

1. Supplemental Restraint System
“Airbag”
Airbag system wiring harness is routed near the A.B.S.
control module, A.B.S. sensor and hydraulic control unit.
CAUTION:

All Airbag system wiring harness and connectors
are colored yellow. Do not use electrical test equip-
ment on these circuit.

Be careful not to damage Airbag system wiring har-
ness when servicing the A.B.S. control module, A.B.S.
sensor and hydraulic control unit.
2. Pre-inspection
Before performing diagnostics, check the following items
which might affect A.B.S. problems:
1. POWER SUPPLY
1) Measure battery voltage and specific gravity of electro-
lyte.
Standard voltage: 12 V, or more
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.
2. BRAKE FLUID
1) Check brake fluid level.
2) Check brake fluid leakage.
3. BRAKE DRAG
Check brake drag.
4. BRAKE PAD AND ROTOR
Check brake pad and rotor.
5. TIRE SPECIFICATIONS, TIRE WEAR AND AIR
PRESSURE
Check tire specifications, tire wear and air pressure. to 4-2 [S1A0].>
2
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1. Supplemental Restraint System“Airbag”- 2. Pre-inspection

1. Supplemental Restraint System
“Airbag”
Airbag system wiring harness is routed near the A.B.S.
control module, A.B.S. sensor and hydraulic control unit.
CAUTION:

All Airbag system wiring harness and connectors
are colored yellow. Do not use electrical test equip-
ment on these circuit.

Be careful not to damage Airbag system wiring har-
ness when servicing the A.B.S. control module, A.B.S.
sensor and hydraulic control unit.
2. Pre-inspection
Before performing diagnostics, check the following items
which might affect A.B.S. problems:
1. POWER SUPPLY
1) Measure battery voltage and specific gravity of electro-
lyte.
Standard voltage: 12 V, or more
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.
2. BRAKE FLUID
1) Check brake fluid level.
2) Check brake fluid leakage.
3. BRAKE DRAG
Check brake drag.
4. BRAKE PAD AND ROTOR
Check brake pad and rotor.
5. TIRE SPECIFICATIONS, TIRE WEAR AND AIR
PRESSURE
Check tire specifications, tire wear and air pressure. to 4-2 [S1A0].>
2
4-4aBRAKES
1. Supplemental Restraint System“Airbag”- 2. Pre-inspection

3. Electrical Components Location
B4M0229A
1Hydraulic control unit

2G sensor (AWD MT model)

3A.B.S. control module

4Warning light
5Tone wheel

6A.B.S. sensor

7Diagnosis connector
G4M0766G4M0767G4M0917
B4M0574AG4M0769B4M0231A
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3. Electrical Components Location

4. Schematic
B4M0647A
1Hydraulic control unit

2Motor

3Motor relay

4Front left solenoid valve

5Front right solenoid valve

6Rear solenoid valve

7Valve relay

8AT control module

9A.B.S. control module

10Warning light
11Stop light

12Stop light switch

13G sensor (AWD MT model)

14Ignition switch

15Battery

16Front left sensor

17Front right sensor

18Rear left sensor

19Rear right sensor

20Diagnosis connector
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4. Schematic

5. Control Module I/O Signal
1. I/O SIGNAL VOLTAGE
G4M0685
ContentsTerminal
No.Ignition
switch ON,
engine
OFFInput/output signals
Measured value Measuring conditions
A.B.S.
sensorFront left wheel 22
0 V 0.12—1V
No. 22—No. 4
(When it is 10 Hz.)
GND 4
Front right wheel 23
0 V 0.12—1V
No. 23—No. 21
(When it is 10 Hz.)
GND 21
Rear left wheel 8
0 V 0.12—1V
No. 8—No. 9
(When it is 10 Hz.)
GND 9
Rear right wheel 24
0 V 0.12—1V
No. 24—No. 26
(When it is 10 Hz.)
GND 26
G sensor (AWD MT model) 13 10—12 V 0 V When slanting about 14°—21.3°(θ)
Diagnosis connector30
—— —
31
Stop light switch 25 0 V 10—12 V When brake pedal is depressed.
Motor monitoring 14 0 V 10—12 V When motor operates.
Valve power supply monitoring 32 10—12 V 10—12 V Ignition switch ON*1
Hydraulic
control
unitSolenoidFront left
wheel210—12 V 0 V
When solenoid is energized to
produce output. Front right
wheel35 10—12 V 0 V
Rear wheel 18 10—12 V 0 V
Valve relay coil 27 0 V 0 V Ignition switch ON*2
Motor relay coil 28 10—12 V 0 VWhen motor operates to produce
output.
Warning light 29 10—12 V 10—12 V Ignition switch ON*3
Power
supplyIgnition 1 10—12 V 10—12 V Ignition switch ON
Relay coil (valve,
motor, etc.)17 10—12 V 10—12 V Ignition switch ON
Grounding line10 0V 0V—
20 0V 0V—
34 0V 0V—
*1: When ignition switch is OFF or the A.B.S. system is inactive: 0 V
*2: When ignition switch is OFF or the A.B.S. system is inactive: 10—12 V
*3: When ignition switch is OFF or the A.B.S. system is inactive, or during 1.5 seconds from ignition switch ON: 0 V
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5. Control Module I/O Signal

B: INSPECTION MODE
The on-board diagnosis system is designed to detect prob-
lems after the vehicle has been driven at 10 km/h (6 MPH)
or more for at least 20 seconds. If a problem is found, the
A.B.S. warning light will illuminate to inform the driver of the
occurrence of a problem. When the warning light is on, the
A.B.S. system will be inactive and the normal braking func-
tion will work. It is possible for a maximum of three trouble
codes to be stored in memory until cleared.
B4M0082A
C: TROUBLE CODES
When on-board diagnosis of the A.B.S. control module
detects a problem, the information (up to a maximum of
three) will be stored in the EEP ROM as a trouble code.
When there are more than three, the most recent three will
be stored. (Stored codes will stay in memory until they are
cleared.)
1. CALLING UP A TROUBLE CODE
1) Take out diagnosis connector from side of driver’s seat
heater unit.
2) Turn ignition switch OFF.
3) Connect diagnosis connector terminal 6 (terminal L) to
diagnosis terminal.
4) Turn ignition switch ON.
5) A.B.S. warning light is set in the diagnostic mode and
blinks to identify trouble code.
6) After the start code (11) is shown, the trouble codes will
be shown in order of the last information first.
These repeat for a maximum of 5 minutes.
NOTE:
When there are no trouble codes in memory, only the start
code (11) is shown.
B4M0232A
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6. Diagnostics Chart for On-board Diagnosis System

7. Diagnostics Chart with Trouble Code
Trouble code Contents of diagnosis Ref. to 4-4a
NONE: A
[Warning light OFF]Trouble in warning light drive circuit
(Warning light is not on for 1.5 seconds after ignition switch is on.)[T7A0]
NONE: B
[Warning light ON] or
[Abnormal trouble code output]Trouble in warning light drive circuit [T7B0]
11Start code:

Trouble code is shown after start code.

Only start code is shown in normal condition.—
21
Faulty A.B.S. sensor
(Open circuit or input voltage
excessive)Front right wheel sensor [T7C0]
23 Front left wheel sensor [T7C0]
25 Rear right wheel sensor [T7C0]
27 Rear left wheel sensor [T7C0]
22
Faulty A.B.S. sensor
(When there is no open circuit or
speed signal input.)Front right wheel sensor [T7D0]
24 Front left wheel sensor [T7D0]
26 Rear right wheel sensor [T7D0]
28 Rear left wheel sensor [T7D0]
29 Faulty tone wheel, etc. [T7E0]
31
Faulty solenoid valve circuit(s) in
hydraulic control unitFront right wheel control [T7F0]
33 Front left wheel control [T7F0]
39 Rear wheels control [T7F0]
41 Faulty A.B.S. control module [T7G0]
42 Source voltage is low. [T7H0]
51 Faulty valve relay [T7I0]
52 Faulty hydraulic motor and/or motor relay [T7J0]
54 Faulty stop light circuit [T7K0]
56 Use of improper A.B.S. control module specification, or faulty G sensor [T7L0]
NOTE:
After diagnostics is completed, make sure to clear memory.
Make sure only start code (11) is shown after memory is
cleared.
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7. Diagnostics Chart with Trouble Code