1995 SUBARU LEGACY ecu

OBD0404
AQ: DTC P0725
—ENGINE SPEED INPUT CIRCUIT
MALFUNCTION (ATNE)—
DESCRIPTION:
The engine speed signal is sent to TCM from ECM. This
signal is used for lock-up clutch control and line pressure
control.
DTC DETECTING CONDITION:

Two consecutive trips with fault
TROUBLE SYMPTOM:

No lock-up occurs. (after engine warm-up)

AT diagnostic indicator light (AT OIL TEMP indicator
light) remains on when vehicle speed is“0”.
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11. Diagnostics Chart with Trouble Code

DTC DETECTING CONDITION:

Two consecutive trips with fault
TROUBLE SYMPTOM:

Shift point too high or too low; engine brake not effected
in“3”range; excessive shift shock; excessive tight corner
“braking”
1.Check any other DTC (besides DTC P0731,
P0732, P0733, P0734) on display.
2.Check throttle position sensor circuit. “3-2 [T7L0]”.>
3.Check vehicle speed sensor 1 circuit. “3-2 [T7M0]”.>
4.Check vehicle speed sensor 2 circuit. “3-2 [T7N0]”.>
5.Check engine speed input circuit. [T7I0]”.>
CAUTION:
After repair or replacement of faulty parts, conduct
CLEAR MEMORY and INSPECTION MODES. [T3D0] and [T3E0].>




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11. Diagnostics Chart with Trouble Code

OBD0605
AV: DTC P0740
—TORQUE CONVERTER CLUTCH SYSTEM
MALFUNCTION (LU
—F)—
DESCRIPTION:
The lock-up engaging and disengaging conditions are set
for each gear shift range, gear position and shift pattern
and correspond to the throttle position and vehicle speed,
and the duty solenoid is electronically controlled by TCM
controls the lock-up clutch. The lock-up clutch engagement
and disengagement are controlled by the lock-up control
valve.
DTC DETECTING CONDITION:

Two consecutive trips with fault
TROUBLE SYMPTOM:

No lock-up occurs. (after engine warm-up)

No shift or excessive tight corner“braking”
289
2-7ON-BOARD DIAGNOSTICS II SYSTEM
11. Diagnostics Chart with Trouble Code

OBD0411
AW: DTC P0743
—TORQUE CONVERTER CLUTCH SYSTEM
(DUTY SOLENOID B) ELECTRICAL (LU)—
OBD0412A
DESCRIPTION:

This solenoid is mounted to the control valve, and its
duty ratio is controlled by the signal sent from TCM. It then
controls the lock-up control valve to provide smooth
engagement and disengagement of the lock-up clutch.

Regulates the hydraulic pressure of the lock-up clutch
and operates in three modes (open, smooth and lock-up).
DTC DETECTING CONDITION:

Two consecutive trips with fault
TROUBLE SYMPTOM:

No“locking-up”(after engine warm-up)
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11. Diagnostics Chart with Trouble Code

OBD0422
AX: DTC P0748
—PRESSURE CONTROL SOLENOID (DUTY
SOLENOID A) ELECTRICAL (PL)—
OBD0048B
DESCRIPTION:

This solenoid is mounted to the control valve, and its
duty ratio is controlled by the signal sent from TCM. This
solenoid then controls the pressure modifier valve and
pressure regulator valve to adjust the line pressure to an
optimum pressure level suitable for operating conditions.

Regulates the line pressure according to driving condi-
tions.
DTC DETECTING CONDITION:

Two consecutive trips with fault
TROUBLE SYMPTOM:

Excessive shift shock
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11. Diagnostics Chart with Trouble Code

OBD0434
AY: DTC P0753
—SHIFT SOLENOID A (SHIFT SOLENOID 1)
ELECTRICAL (SFT1)—
OBD0048C
DESCRIPTION:

These solenoids are mounted to the control valve. They
are turned ON or OFF according to signals sent from the
TCM. The gear positions are changed according to the ON
and OFF condition of these solenoids.

Controls shift stage by turning solenoid ON/OFF. Rela-
tionship between solenoid operation and shifting stage is
shown in table below. When shifting, timing is controlled for
each solenoid to reduce shock.
DTC DETECTING CONDITION:

Two consecutive trips with fault
TROUBLE SYMPTOM:

No shift
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11. Diagnostics Chart with Trouble Code

OBD0442
AZ: DTC P0758
—SHIFT SOLENOID B (SHIFT SOLENOID 2)
ELECTRICAL (SFT2)—
OBD0048D
DESCRIPTION:

These solenoids are mounted to the control valve. They
are turned ON or OFF according to signals sent from the
TCM. The gear positions are changed according to the ON
and OFF condition of these solenoids.

Controls shift stage by turning solenoid ON/OFF. Rela-
tionship between solenoid operation and shifting stage is
shown in table below. When shifting, timing is controlled for
each solenoid to reduce shock.
DTC DETECTING CONDITION:

Two consecutive trips with fault
TROUBLE SYMPTOM:

No shift
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2-7ON-BOARD DIAGNOSTICS II SYSTEM
11. Diagnostics Chart with Trouble Code

OBD0611
BA: DTC P0760
—SHIFT SOLENOID C (SHIFT SOLENOID 3)
MALFUNCTION (OVR
—F)—
OBD0048E
DESCRIPTION:

This solenoid is also mounted to the control valve. It is
turned ON or OFF according to the signal sent from the
TCM. This operation controls the engagement and disen-
gagement of the overrunning clutch.

Controls 3-2 shift timing and overrunning clutch opera-
tion. Shift timing is controlled by controlling release speed
of oil pressure to reduce shock while down shifting. The
overrunning clutch is controlled so that it will operate dur-
ing coasting to apply engine brake.
DTC DETECTING CONDITION:

Two consecutive trips with fault
TROUBLE SYMPTOM:

Ineffective engine brake with selector lever in“3”
302
2-7ON-BOARD DIAGNOSTICS II SYSTEM
11. Diagnostics Chart with Trouble Code