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2. I/O SIGNAL DIAGRAM
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5. Control Module I/O Signal
Page 1634 of 2248
6. Diagnostics Chart for On-board
Diagnosis System
A: BASIC DIAGNOSTICS PROCEDURE
NOTE:
To check harness for broken wires or short circuits,
shake it while holding it or the connector.
When A.B.S. warning light illuminates, read and record
trouble code indicated by A.B.S. warning light.
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6. Diagnostics Chart for On-board Diagnosis System
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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
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B4M0082A
2. CLEARING MEMORY
1) After calling up a trouble code, disconnect diagnosis
connector terminal 6 (terminal L) from diagnosis terminal.
2) Repeat 3 times within approx. 12 seconds; connecting
and disconnecting terminal 6 (terminal L) and diagnosis
terminal for at least 0.2 seconds each time.
B4M0233B
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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6. Diagnostics Chart for On-board Diagnosis System
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![SUBARU LEGACY 1995 Service Repair Manual 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 SUBARU LEGACY 1995 Service Repair Manual 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](/manual-img/17/57432/w960_57432-1636.png)
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
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A: TROUBLE CODE (NONE: A)
—TROUBLE IN WARNING LIGHT DRIVE
CIRCUIT—
DIAGNOSIS:
Faulty A.B.S. warning light
Faulty harness connector
Faulty A.B.S. control module
Faulty valve relay
TROUBLE SYMPTOM:
Warning light does not illuminate.
Impossible to read trouble code.
NOTE:
When ignition key is on, warning light should turn off after
1.5 seconds if system is normal.
1. Check A.B.S. warning light power supply.
OK
Not OK
Repair A.B.S. warning light power line.
2. Check input voltage of A.B.S. control module
and hydraulic control unit from A.B.S. warn-
ing light.
OK
Not OK
Repair harness/connector.
3. Check ground line of A.B.S. control module
and hydraulic control unit.
OK
Not OK
Repair ground line.
4. Check valve relay.
OK
Not OK
Replace valve relay.
Replace A.B.S. control module and hydraulic control
unit.
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7. Diagnostics Chart with Trouble Code
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B4M0575
B4M0235B
1. CHECK A.B.S. WARNING LIGHT POWER SUPPLY.
1) Turn ignition switch OFF.
2) Disconnect combination meter.
3) Check A.B.S. warning light valve.
4) Turn ignition switch ON.
5) Measure voltage between combination meter connector
and body.
Connector & terminal / Specified voltage:
(i14) No. 11 — Body / 10 — 12 V
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7. Diagnostics Chart with Trouble Code
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B4M0236B
2. CHECK INPUT VOLTAGE OF A.B.S. CONTROL
MODULE AND HYDRAULIC CONTROL UNIT FROM
A.B.S. WARNING LIGHT.
1) Turn ignition switch OFF and remove combination
meter.
2) Disconnect connector from A.B.S. control module and
hydraulic control unit.
3) Turn ignition switch ON.
4) Measure voltage between A.B.S. control module and
body, and between hydraulic control unit and body.
Connector & terminal / Specified voltage:
(P3) No. 29—body / 10—12 V
(F9) No. 10—body / 10—12 V
B4M0237B
3. CHECK GROUND LINE OF A.B.S. CONTROL
MODULE AND HYDRAULIC CONTROL UNIT.
Measure resistance between A.B.S. control module and
body, and between hydraulic control unit and body.
Connector & terminal / Specified resistance:
(P3) No. 10—body / 0Ω
(P3) No. 20—body / 0Ω
(P3) No. 34—body / 0Ω
(F9) No. 8—body / 0Ω
G4M0690
4. CHECK VALVE RELAY.
1) Remove valve relay.
2) Attach circuit tester probes to terminals, as shown in
figure.
3) Measure resistance between respective terminals.
Terminal / Specified resistance:
No. 87—No. 30 / 0Ω(when 12 volts applied.)
No. 87—No.30/1MΩ(when no volts applied.)
No. 87a—No.30/1MΩ(when 12 volts applied.)
No. 87a—No. 30 / 0Ω(when no volts applied.)
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7. Diagnostics Chart with Trouble Code