SUBARU LEGACY 1995 Service Repair Manual

OBD0599
AR: DTC P0731
—GEAR 1 INCORRECT RATIO (GR
—1)—
OBD0600
AS: DTC P0732
—GEAR 2 INCORRECT RATIO (GR
—2)—
OBD0601
AT: DTC P0733
—GEAR 3 INCORRECT RATIO (GR
—3)—
OBD0602
AU: DTC P0734
—GEAR 4 INCORRECT RATIO (GR
—4)—
285
2-7ON-BOARD DIAGNOSTICS II SYSTEM
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. <Ref. to
“3-2 [T7L0]”.>
3.Check vehicle speed sensor 1 circuit. <Ref. to
“3-2 [T7M0]”.>
4.Check vehicle speed sensor 2 circuit. <Ref. to
“3-2 [T7N0]”.>
5.Check engine speed input circuit. <Ref. to“3-2
[T7I0]”.>
CAUTION:
After repair or replacement of faulty parts, conduct
CLEAR MEMORY and INSPECTION MODES. <Ref. to
[T3D0] and [T3E0].>




286
2-7ON-BOARD DIAGNOSTICS II SYSTEM
11. Diagnostics Chart with Trouble Code

WIRING DIAGRAM:
OBD0604
1CHECK ANY OTHER DTC (BESIDES DTC
P0731, P0732, P0733, P0734) ON DISPLAY.
: Is there any other DTC on display?
: Inspect relevant DTC using“11. Diagnostics Chart
with Trouble Code”.
: Go to step 2.
287
2-7ON-BOARD DIAGNOSTICS II SYSTEM
11. Diagnostics Chart with Trouble Code

2CHECK THROTTLE POSITION SENSOR CIR-
CUIT.
: Is there any trouble in throttle position sen-
sor circuit?
: Repair or replace throttle position sensor circuit.
: Go to step 3.
3
CHECK VEHICLE SPEED SENSOR 1 CIRCUIT.
: Is there any trouble in vehicle speed sensor
1 circuit?
: Repair or replace vehicle speed sensor 1 circuit.
: Go to step 4.
4
CHECK VEHICLE SPEED SENSOR 2 CIRCUIT.
: Is there any trouble in vehicle speed sensor
2 circuit?
: Repair or replace vehicle speed sensor 2 circuit.
: Go to step 5.
5
CHECK ENGINE SPEED INPUT CIRCUIT.
: Is there any trouble in engine speed input
circuit?
: Repair or replace engine speed input circuit.
: Go to next.
: Is there poor contact in TCM connector?
: Repair poor contact in TCM connector.
: Go to next.
: Is there any mechanical trouble in automatic
transmission?
: Repair or replace automatic transmission.
: Replace TCM with a new one.
288
2-7ON-BOARD DIAGNOSTICS II SYSTEM
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

1.Check any other DTC (besides DTC P0740) on
display.
2.Check duty solenoid B circuit. <Ref. to“3-2
[T7B0]”.>
3.Check throttle position sensor circuit. <Ref. to
“3-2 [T7L0]”.>
4.Check vehicle speed sensor 1 circuit. <Ref. to
“3-2 [T7M0]”.>
5.Check vehicle speed sensor 2 circuit. <Ref. to
“3-2 [T7N0]”.>
6.Check engine speed input circuit. <Ref. to“3-2
[T7I0]”.>
7.Check inhibitor switch circuit. <Ref. to“AN:
DTC P0705 [T11AN0]”.>
8.Check brake light switch circuit. <Ref. to“AM:
DTC P0703 [T11AM0]”.>
9.Check ATF temperature sensor circuit. <Ref. to
“3-2 [T7G0]”.>
CAUTION:
After repair or replacement of faulty parts, conduct
CLEAR MEMORY and INSPECTION MODES. <Ref. to
[T3D0] and [T3E0].>








290
2-7ON-BOARD DIAGNOSTICS II SYSTEM
11. Diagnostics Chart with Trouble Code

WIRING DIAGRAM:
OBD0606
1CHECK ANY OTHER DTC (BESIDES DTC
P0740) ON DISPLAY.
: Is there any other DTC on display?
: Inspect the relevant DTC using“11. Diagnostics
Chart with Trouble Code”.
: Go to step 2.
291
2-7ON-BOARD DIAGNOSTICS II SYSTEM
11. Diagnostics Chart with Trouble Code

2
CHECK DUTY SOLENOID B CIRCUIT.
: Is there any trouble in duty solenoid B cir-
cuit?
: Repair or replace duty solenoid B circuit.
: Go to step 3.
3CHECK THROTTLE POSITION SENSOR CIR-
CUIT.
: Is there any trouble in throttle position sen-
sor circuit?
: Repair or replace throttle position sensor circuit.
: Go to step 4.
4
CHECK VEHICLE SPEED SENSOR 1 CIRCUIT.
: Is there any trouble in vehicle speed sensor
1 circuit?
: Repair or replace vehicle speed sensor 1 circuit.
: Go to step 5.
5
CHECK VEHICLE SPEED SENSOR 2 CIRCUIT.
: Is there any trouble in vehicle speed sensor
2 circuit?
: Repair or replace vehicle speed sensor 2 circuit.
: Go to step 6.
6
CHECK ENGINE SPEED INPUT CIRCUIT.
: Is there any trouble in engine speed input
circuit?
: Repair or replace engine speed input circuit.
: Go to step 7.
292
2-7ON-BOARD DIAGNOSTICS II SYSTEM
11. Diagnostics Chart with Trouble Code

7
CHECK INHIBITOR SWITCH CIRCUIT.
: Is there any trouble in inhibitor switch cir-
cuit?
: Repair or replace inhibitor switch circuit.
: Go to step 8.
8
CHECK BRAKE LIGHT SWITCH CIRCUIT.
: Is there any trouble in brake light switch cir-
cuit?
: Repair or replace brake light switch circuit.
: Go to step 9.
9CHECK ATF TEMPERATURE SENSOR CIR-
CUIT.
: Is there any trouble in ATF temperature sen-
sor circuit?
: Repair or replace ATF temperature sensor circuit.
: Go to next.
: Is there poor contact in TCM connector?
: Repair poor contact in TCM connector.
: Go to next.
: Is there any mechanical trouble in automatic
transmission?
: Repair or replace automatic transmission.
: Replace TCM with a new one.
293
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)
294
2-7ON-BOARD DIAGNOSTICS II SYSTEM
11. Diagnostics Chart with Trouble Code