1997 SUBARU LEGACY automatic transmission and differential

5. Transmission Control Module (TCM)
I/O Signal
OBD0093A
Check with ignition switch ON.
ContentConnector
No.Terminal
No.Measuring conditions Voltage (V)
Back-up power supply B56 14 Ignition switch OFF 10—16
Ignition power supplyB54 6
Ignition switch ON (with engine OFF) 10—16
B55 1
Inhibitor switch“P”range switch B56 9Select lever in“P”range Less than 1
Select lever in any other than“P”
range (except“N”range)More than 8
“N”range switch B56 8Select lever in“N”range Less than 1
Select lever in any other than“N”
range (except“P”range)More than 8
“R”range switch B56 10Select lever in“R”range Less than 1
Select lever in any other than“R”
rangeMore than 6
“D”range switch B54 1Select lever in“D”range Less than 1
Select lever in any other than“D”
rangeMore than 6
“3”range switch B54 2Select lever in“3”range Less than 1
Select lever in any other than“3”
rangeMore than 6
“2”range switch B54 3Select lever in“2”range Less than 1
Select lever in any other than“2”
rangeMore than 6
“1”range switch B54 4Select lever in“1”range Less than 1
Select lever in any other than“1”
rangeMore than 6
Diagnosis switch B56 6Diagnosis connector connected Less than 1
Diagnosis connector disconnected More than 6
Brake switch B56 7Brake pedal depressed. More than 10.5
Brake pedal released. Less than 1
ABS signal B56 5ABS switch ON Less than 1
ABS switch OFF More than 6.5
AT diagnostic signal B55 12Ignition switch ON (With engine OFF) Less than 1
Ignition switch ON (With engine ON) More than 10
9
3-2AUTOMATIC TRANSMISSION AND DIFFERENTIAL
5. Transmission Control Module (TCM) I/O Signal

ContentConnector
No.Terminal
No.Measuring conditionsVoltage
(V)Resistance to
body
(ohms)
Throttle position
sensorB54 8Throttle fully closed. 0.5±0.2
—
Throttle fully open. 4.6±0.3
Throttle position
sensor power
supplyB56 19Ignition switch ON
(With engine OFF)5.05±0.25—
ATF temperature
sensorB54 10ATF temperature 20°C(68°F) 3.45±0.55 2.1—2.9 k
ATF temperature 80°C (176°F) 1.2±0.2 275—375
Vehicle speed
sensor 1B54 12Vehicle stopped. 0
450—720
Vehicle speed at least 20 km/h (12
MPH)More than 1 (AC range)
Vehicle speed
sensor 2B56 11When vehicle is slowly moved at
least 2 meters (7ft).Less than 1)More than 9—
Engine speed
signalB54 5Ignition switch ON (with engine
OFF).More than 10.5
—
Ignition switch ON (with engine ON). 8—11
Cruise set signal B56 3When cruise control is set (SET
lamp ON).Less than 1
—
When cruise control is not set (SET
lamp OFF).More than 6.5
Torque control
signalB55 16 Ignition switch ON 5±1—
Torque control cut
signalB56 16 Ignition switch ON 6—9—
Mass air flow
signalB54 9 Engine idling after warm-up 0.5—1.2—
Shift solenoid 1 B55 141st or 4th gear More than 9
20—32
2nd or 3rd gear Less than 1
Shift solenoid 2 B55 131st or 2nd gear More than 9
20—32
3rd or 4th gear Less than 1
Shift solenoid 3 B55 15Select lever in“N”range (with
throttle fully closed).Less than 1
20—32
Select lever in“D”range (with
throttle fully closed).More than 9
Duty solenoid A B55 8Throttle fully closed (with engine
OFF) after warm-up.1.5—4.0
2.0—4.5
Throttle fully open (with engine
OFF) after warm-up.Less than 1
Dropping resistor B55 7Throttle fully closed (with engine
OFF) after warm-up.More than 8.5
12—18
Throttle fully open (with engine
OFF) after warm-up.Less than 1
Duty solenoid B B55 5When lock up occurs. More than 8.5
9—17
When lock up is released. Less than 0.5
Duty solenoid C
(AWD model only)B55 3Fuse on FWD switch More than 8.5
9—17 Fuse removed from FWD switch
(with throttle fully open and with
select lever in 1st gear).Less than 0.5
Sensor ground
line 1B54 7—0 Less than 1
Sensor ground
line 2B56 20—0 Less than 1
System ground
lineB56 1—0 Less than 1
Power system
ground lineB55 10—0 Less than 1
FWD switch
(AWD model only)B56 2Fuse removed. 6—9.1
—
Fuse installed. Less than 1
10
3-2AUTOMATIC TRANSMISSION AND DIFFERENTIAL
5. Transmission Control Module (TCM) I/O Signal

6. Diagnostic Chart for On-board
Diagnostic System
A: BASIC DIAGNOSTICS PROCEDURE
TROUBLE OCCURS.
INTERVIEW
1. Oil level check [W2A1], [W2A2].>
2. Oil leak check [W2A3].>
3. Brake band adjustment 3-2 [W2B1].>
4. Stall test
5. Line pressure test [W3C0].>
6. Transfer clutch pressure test

7. Time lag test [W3B0].>
8. Road test
BASIC CHECKS
TROUBLE INDICATION (AT OIL
TEMP INDICATOR)
Not indicated.
Indicated.
ON-BOARD
DIAGNOSTICS
Trouble code Inspection using General Diagnostic
Table 3-2 [T900].
OK
Inspection using Diagnostic Chart
with Select Monitor 3-2 [T800]
Not OK
No trouble code
Repair.Check in
accordance
trouble code 3-2
[T700].

CLEAR MEMORY
Confirmation test
(ON-BOARD DIAGNOSTICS)
No trouble codeTrouble code
End








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6. Diagnostic Chart for On-board Diagnostic System

B: ABNORMAL DISPLAY ON AT OIL TEMP
INDICATOR
When any on-board diagnostic item is malfunctioning, the
display on the AT OIL TEMP indicator blinks immediately
after the engine starts.
The malfunctioning part or unit can be determined by a
trouble code during on-board diagnostic operation. Prob-
lems which occurred previously can also be identified
through the memory function.
If the AT OIL TEMP indicator does not show a problem
(although a problem is occurring), the problem can be
determined by checking the performance characteristics of
each sensor using the select monitor.
Indicator signal is as shown in the figure.
WARNING:
Warning can be noticed only when the engine is ini-
tially started.
B3M0410A
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3-2AUTOMATIC TRANSMISSION AND DIFFERENTIAL
6. Diagnostic Chart for On-board Diagnostic System

C: ON-BOARD DIAGNOSTICS
* : Blinks every 0.125 (1/8) seconds (until ignition switch is turned OFF).
** : Blinks every 0.25 (1/4) seconds (until ignition switch is turned OFF).
*** : Plug in diagnosis terminal to diagnosis connector No. 5 located below instrument lower cover.
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3-2AUTOMATIC TRANSMISSION AND DIFFERENTIAL
6. Diagnostic Chart for On-board Diagnostic System

D: LIST OF TROUBLE CODE
1. TROUBLE CODE
Trouble code Item Content of diagnosisAbbr.
(Select monitor)Page
11 Duty solenoid ADetects open or shorted drive
circuit, as well as valve seizure.PLDTY 16
12 Duty solenoid BDetects open or shorted drive
circuit, as well as valve seizure.LUDTY 20
13 Shift solenoid 3Detects open or shorted drive
circuit, as well as valve seizure.OVR 24
14 Shift solenoid 2Detects open or shorted drive
circuit, as well as valve seizure.SFT2 26
15 Shift solenoid 1Detects open or shorted drive
circuit, as well as valve seizure.SFT1 28
21 ATF temperature sensorDetects open or shorted input
signal circuit.ATFT 30
22 Mass air flow signalDetects open or shorted input
signal circuit.AFM 33
23 Engine speed signalDetects open or shorted input
signal circuit.EREV 35
24 Duty solenoid CDetects open or shorted drive
circuit, as well as valve seizure.4WDTY 37
25 Torque control signalDetects open or shorted input
signal circuit.TQ.CT 39
31 Throttle position sensorDetects open or shorted input
signal circuit.THV 41
32 Vehicle speed sensor 1Detects open or shorted input
signal circuit.VSP1 44
33 Vehicle speed sensor 2Detects open or shorted input
signal circuit.VSP2 48
14
3-2AUTOMATIC TRANSMISSION AND DIFFERENTIAL
6. Diagnostic Chart for On-board Diagnostic System

2. HOW TO READ TROUBLE CODE OF INDICATOR
LIGHT
The AT OIL TEMP indicator light flashes the code corre-
sponding to the faulty part.
The long segment (1.2 sec on) indicates a“ten”, and the
short segment (0.2 sec on) signifies a“one”.
B3M0193A
E: CLEAR MEMORY
Current trouble codes shown on the display are cleared by
turning the ignition switch OFF after conducting on-board
diagnostic operation. Previous trouble codes, however,
cannot be cleared since they are stored in the TCM
memory which is operating on the back-up power supply.
These trouble codes can be cleared by removing the speci-
fied fuse (located under the right lower portion of the instru-
ment panel).
CLEAR MEMORY:
Removal of No. 14 fuse (for at least one minute)

The No. 14 fuse is located in the line to the memory
back-up power supply of the TCM and ABS/TCS control
module. Removal of this fuse clears the previous trouble
codes stored in the TCM and ABS/TCS control module
memory.

Be sure to remove the No. 14 fuse for at least the speci-
fied length of time. Otherwise, trouble codes may not be
cleared.
15
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6. Diagnostic Chart for On-board Diagnostic System

7. Diagnostic Chart with Trouble Code
A: TROUBLE CODE 11
—DUTY SOLENOID A—
DIAGNOSIS:
Output signal circuit of duty solenoid A or resistor is open
or shorted.
TROUBLE SYMPTOM:
Excessive shift shock
1. Check harnesses and connectors between
TCM and duty solenoid A and between
resistor.
OK
Not OK
Repair or replace harness connectors.
2. Check duty solenoid A’s ground line.
OK
Not OK
Repair ground line.
3. Check resistor.
OK
Not OK
Check and replace resistor if necessary.
4. Check duty solenoid A.
OK
Not OK
Replace duty solenoid A.
5. Check output signal emitted from TCM.
OK
Not OK

Repair TCM connector terminal poor contact.

Replace TCM.

Repair TCM connector terminal poor contact.
OBD0424





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3-2AUTOMATIC TRANSMISSION AND DIFFERENTIAL
7. Diagnostic Chart with Trouble Code