check engine light SUBARU LEGACY 1997 Service Manual PDF

OBD0396A
3. CHECK INPUT SIGNAL FOR TCM.
1) Connect connectors to TCM and transmission.
2) Lift-up or raise the vehicle and place safety stands.
CAUTION:
On AWD models, raise all wheels off floor.
3) Push the TCS OFF switch to ON. (With TCS models)
4) Start the engine and set vehicle in 20 km/h (12 MPH)
condition.
5) Measure voltage between TCM connector terminals.
Connector & terminal / Specified voltage:
(B54) No. 12—No. 7 / AC 1 V, or more
NOTE:
The speed difference between front and rear wheels may
light either the ABS or the ABS/TCS warning light, but this
indicates no malfunctions. When AT control diagnosis is
finished, perform the ABS or the ABS/TCS memory clear-
ance procedure of self-diagnosis system.
or 4-4d [T6D2] or [T9J0].>
OBD0145A
B3M0413
OBD0399

Using Subaru select monitor:
(1) Connect connectors to TCM and transmission.
(2) Turn ignition switch to OFF.
(3) Connect the Subaru select monitor to data link con-
nector.
(4) Lift-up or raise the vehicle and place safety stands.
CAUTION:
On AWD models, raise all wheels off floor.
(5) Turn ignition switch to ON and Subaru select moni-
tor switch to ON.
(6) Push the TCS OFF switch to ON. (With TCS mod-
els)
(7) Start the engine and operate at constant speed.
(8) Read data on Subaru select monitor.
(9) Designate mode using function key.
Function mode: F02 or F03
SPECIFIED DATA:
F02: Compare speedometer with monitor indica-
tions.
F03: Compare speedometer with monitor indica-
tions.

F02: Vehicle speed is indicated in“m/h”.

F03: Vehicle speed is indicated in“km/h”.
NOTE:
The speed difference between front and rear wheels may
light either the ABS or the ABS/TCS warning light, but this
indicates no malfunctions. When AT control diagnosis is
finished, perform the ABS or the ABS/TCS memory clear-
ance procedure of self-diagnosis system.
or 4-4d [T6D2] or [T9J0].>
46
3-2AUTOMATIC TRANSMISSION AND DIFFERENTIAL
7. Diagnostic Chart with Trouble Code

B3M0289
3. CHECK VEHICLE SPEED SENSOR 2.
1) Install combination meter.
2) Connect connector to TCM.
3) Lift-up the vehicle and place safety stand.
CAUTION:
On AWD models, raise all wheels off floor.
4) Disconnect connector from vehicle speed sensor 2.
5) Measure resistance between terminals of vehicle speed
sensor 2.
Terminals / Specified resistance:
(B17) No. 1—No. 2 / 350—450Ω
No. 1—Body/1MΩ, or more
No. 2—Body/1MΩ, or more
B3M0256
6) Push the TCS OFF switch to ON. (With TCS models)
7) Start the engine and set vehicle in 20 km/h (12 MPH)
condition.
8) Measure output signal of vehicle speed sensor 2.
WARNING:
Be careful not to be caught up by the running wheels.
9) Using a voltage meter; measure voltage between termi-
nals of vehicle speed sensor 2.
Terminals / Specified voltage:
(B17) No. 1—No. 2 / AC 2 V, or more
NOTE:
The speed difference between front and rear wheels may
light either the ABS or the ABS/TCS warning light, but this
indicates no malfunctions. When AT control diagnosis is
finished, perform the ABS or the ABS/TCS memory clear-
ance procedure of self-diagnosis system.
or 4-4d [T6D2] or [T9J0].>
50
3-2AUTOMATIC TRANSMISSION AND DIFFERENTIAL
7. Diagnostic Chart with Trouble Code

B3M0257

Using oscilloscope:
(1) Install combination meter.
(2) Connect connector to TCM.
(3) Lift-up the vehicle and place safety stand.
WARNING:
On AWD models, make sure that all wheels are raised
off floor.
(4) Set oscilloscope to vehicle speed sensor 2.
Connector & terminal / No. 1—No. 2
B3M0254A
(5) Push the TCS OFF switch to ON. (With TCS mod-
els)
(6) Start the engine, and drive the wheels slowly.
(7) Measure signal voltage indicated on oscilloscope.
Specified voltage: AC 2 V, or more
NOTE:
The speed difference between front and rear wheels may
light either the ABS or the ABS/TCS warning light, but this
indicates no malfunctions. When AT control diagnosis is
finished, perform the ABS or the ABS/TCS memory clear-
ance procedure of self-diagnosis system.
or 4-4d [T6D2] or [T9J0].>
B3M0369A
4. CHECK INPUT SIGNAL FOR TCM.
1) Connect connector to vehicle speed sensor 2.
2) Lift-up the vehicle or set the vehicle on free roller.
CAUTION:
On AWD models, raise all wheels off floor.
3) Push the TCS OFF switch to ON. (With TCS models)
4) Start the engine, and drive the wheels slowly.
5) Measure voltage between TCM and body.
Connector & terminal / Specified voltage:
(B56) No. 11—Body / Less than 1↔
more than 9 V
NOTE:
The speed difference between front and rear wheels may
light either the ABS or the ABS/TCS warning light, but this
indicates no malfunctions. When AT control diagnosis is
finished, perform the ABS or the ABS/TCS memory clear-
ance procedure of self-diagnosis system.
or 4-4d [T6D2] or [T9J0].>
51
3-2AUTOMATIC TRANSMISSION AND DIFFERENTIAL
7. Diagnostic Chart with Trouble Code

B: CHECK LIST FOR INTERVIEW
Check the following items about the vehicle’s state.
1. THE STATE OF THE WARNING LIGHTS
a. ABS warning light

1Is always on.2Sometimes comes on.3Comes on only once.4Does not come on.
When/how long does it come on?
Ignition key
position
1Lock2Acc3On (before starting engine)4Start5On after starting (Engine: run)
6On after starting (Engine: stop)
Timing
1Immediately after ignition is on.2Immediately after ignition starts.
3When advancing (Speedmiles/h,miles/h)4While traveling at a constant speed (Speedmiles/h)
5When decelerating (Speedmiles/h,miles/h)
6When turning (To right, to left, steering angledeg., steering timesec)
7When other electrical parts move (Part name:, Operating condition)
8When moving other electrical parts (Part name:, Operating condition)
b. TCS warning light

1Is always on.2Sometimes comes on.3Comes on only once.4Does not come on.
When does it come on?
Ignition key
position
1Lock2Acc3On (before starting engine)4Start5On after starting (Engine: run)
6On after starting (Engine: stop)
Timing
1Immediately after ignition is on.2Immediately after ignition starts.
3When advancing (Speedmiles/h,miles/h)4While traveling at a constant speed (Speedmiles/h)
5When decelerating (Speedmiles/h,miles/h)
6When turning (To right, to left, steering angledeg., steering timesec)
7When other electrical parts move (Part name:, Operating condition)
8When moving other electrical parts (Part name:, Operating condition)
c. TCS OFF indicator light

1Is always on.2Sometimes comes on.3Comes on only once.4Does not come on.
When/how long does it come on?
Ignition key
position
1Lock2Acc3On (before starting engine)4Start5On after starting (Engine: run)
6On after starting (Engine: stop)
Timing
1Immediately after ignition is on.2Immediately after ignition starts.
3When advancing (Speedmiles/h,miles/h)4While traveling at a constant speed (Speedmiles/h)
5When decelerating (Speedmiles/h,miles/h)
6When turning (To right, to left, steering angledeg., steering timesec)
7When other electrical parts move (Part name:, Operating condition)
8When moving other electrical parts (Part name:, Operating condition)
d. TCS operation indicator light

1Is always on.2Sometimes comes on.3Comes on only once.4Does not come on.
When does it come on?
Ignition key
position
1Lock2Acc3On (before starting engine)4Start5On after starting (Engine: run)
6On after starting (Engine: stop)
Timing
1Immediately after ignition is on.2Immediately after ignition starts.
3When advancing (Speedmiles/h,miles/h)4While traveling at a constant speed (Speedmiles/h)
5When decelerating (Speedmiles/h,miles/h)
6When turning (To right, to left, steering angledeg., steering timesec)
7When other electrical parts move (Part name:, Operating condition)
8When moving other electrical parts (Part name:, Operating condition)
14
4-4bBRAKES
6. Diagnostics Chart for On-board Diagnosis System

7. Diagnostics Chart for Warning Light
Circuit Failure
A: TROUBLE CODE DOES NOT APPEAR.
—TCS WARNING LIGHT COMES ON WHEN
STARTING THE ENGINE.—
1. Check TCS warning light.
OK
Not OK
Repair harness.
2. Check diagnosis terminal.
OK
Not OK
Repair harness.
3. Check diagnosis connector.
OK
Not OK
Repair harness/connector.
Replace ABS/TCS control module.
B4M0385



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7. Diagnostics Chart for Warning Light Circuit Failure

B: ABS AND TCS WARNING LIGHT DO NOT
GO OFF.
—TCS OFF AND TCS OPERATING
INDICATOR LIGHTS COME ON AND GO OFF
PROPERLY WHEN STARTING THE ENGINE,
WHILE ABS WARNING AND TCS WARNING
LIGHTS KEEP ON.—
1. Check brake fluid level.
OK
Not OK
Add to brake fluid.
2. Check brake fluid level sensor.
OK
Not OK
Replace master cylinder.
3. Check harness connector between ABS/TCS
control module and alternator.
OK
Not OK
Replace harness connector.
Replace ABS/TCS control module.
B4M0389



20
4-4bBRAKES
7. Diagnostics Chart for Warning Light Circuit Failure

1. CHECK BRAKE FLUID LEVEL.
Check that brake fluid level is above the MIN indication on
the reservoir tank.
B4M0716A
2. CHECK BRAKE FLUID LEVEL SENSOR.
1) Turn ignition switch OFF.
2) Disconnect connector from brake fluid level sensor.
Connector & terminal / Specified resistance:
(B16) No. 1—No.2/0Ω(Leaving float where it
is.)
(B16) No. 1—No.2/1MΩ(When pushing float
down.)
B4M0717A
3. CHECK HARNESS CONNECTOR BETWEEN ABS/
TCS CONTROL MODULE AND ALTERNATOR.
1) Turn ignition switch OFF.
2) Connect connector from brake fluid level sensor.
3) Disconnect all connectors from ABS/TCS control mod-
ule.
4) Measure voltage between ABS/TCS control module
connector and body.
Connector & terminal / Specified voltage:
(P7) No. 20—body/2Vorless
5) Start the engine.
6) Measure voltage between ABS/TCS control module
connector and body.
Connector & terminal / Specified voltage:
(P7) No. 20—body / 10—14 V
21
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7. Diagnostics Chart for Warning Light Circuit Failure

C: TCS WARNING LIGHT AND TCS
INDICATOR OFF AND TCS OPERATING
INDICATOR LIGHTS COME ON AND GO OFF
PROPERLY, WHILE ABS WARNING LIGHT
DOES NOT GO OFF.
—TCS WARNING LIGHT AND TCS OFF
INDICATOR AND TCS OPERATING
INDICATOR LIGHTS COME ON AND GO OFF
PROPERLY WHEN STARTING THE ENGINE,
WHILE ABS WARNING LIGHT DOES NOT GO
OFF.—
1. Check harness connector between ABS/TCS
control module and ABS warning light.Repair harness connector.
Replace ABS/TCS control module.
B4M0392

22
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7. Diagnostics Chart for Warning Light Circuit Failure

D: ABS WARNING LIGHT ONLY REMAINS
ILLUMINATED.
—WHEN STARTING THE ENGINE, NEITHER
TCS WARNING, TCS OFF INDICATOR NOR
TCS OPERATING INDICATOR LIGHT COMES
ON EVEN ONCE, AND ABS WARNING LIGHT
AND MALFUNCTION INDICATOR LAMP
ILLUMINATE.—
1. Check input voltage of ABS/TCS control mod-
ule.
OK
Not OK
Repair harness/connector.
Replace ABS/TCS control module.
B4M0394

24
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7. Diagnostics Chart for Warning Light Circuit Failure

E: TCS OFF INDICATOR LIGHT DOES NOT
GO OFF.
—ABS WARNING, TCS WARNING AND TCS
OPERATING INDICATOR LIGHTS COME ON
AND GO OFF PROPERLY WHEN STARTING
THE ENGINE, BUT TCS OFF INDICATOR
DOES NOT GO OFF FOR MORE THAN 30
SECONDS AFTER ENGINE RUNNING.—
Does malfunction indicator lamp (Check engine
lamp) come on?
No
Ye s
Conduct OBD II diagnosis.

1. Check harness connector between ABS/TCS
control module and TCS OFF indicator light.
OK
Not OK
Repair harness/connector.
Replace ABS/TCS control module.
B4M0396


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7. Diagnostics Chart for Warning Light Circuit Failure