Subaru Legacy 2002 Service Manual page 1488

DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
BQ: DTC P0734 — GEAR 4 INCORRECT RATIO —
¼ DTC DETECTING CONDITION:
¼ Two consecutive driving cycles with fault
¼ TROUBLE SYMPTOM:
¼ Shift point too high or too low; engine brake not effective in "3" range; excessive shift shock; exces-
sive tight corner "braking"
CAUTION:
After repair or replacement of faulty parts, conduct CLEAR MEMORY MODE <Ref. to EN(H6)-49,
OPERATION, Clear Memory Mode.> and INSPECTION MODE <Ref. to EN(H6)-46, OPERATION,
Inspection Mode.>.
¼ WIRING DIAGRAM:
No.
1 CHECK ANY OTHER DTC ON DISPLAY.
2 CHECK THROTTLE POSITION SENSOR
CIRCUIT.
Check throttle position sensor circuit. <Ref. to
AT-46, DTC 31 THROTTLE POSITION
SENSOR, Diagnostic Procedure with Diag-
nostic Trouble Code (DTC).>
3 CHECK FRONT VEHICLE SPEED SENSOR
CIRCUIT.
Check front vehicle speed sensor circuit.
<Ref. to AT-52, DTC 33 FRONT VEHICLE
SPEED SENSOR, Diagnostic Procedure with
Diagnostic Trouble Code (DTC).>
4 CHECK TORQUE CONVERTER TURBINE
SPEED SENSOR CIRCUIT.
Check torque converter turbine speed sensor
circuit. <Ref. to AT-58, DTC 36 TORQUE
CONVERTER TURBINE SPEED SENSOR,
Diagnostic Procedure with Diagnostic Trouble
Code (DTC).>
5 CHECK POOR CONTACT.
Check poor contact in TCM connector.
6 CHECK MECHANICAL TROUBLE.
Check mechanical trouble in automatic trans-
mission.
Step
Is there any other DTC on
display?
Is there any trouble in
throttle position sensor cir-
cuit?
Is there any trouble in
vehicle speed sensor 2 cir-
cuit?
Is there any trouble in
torque converter turbine
speed sensor circuit?
Is there poor contact in
TCM connector?
Is there any mechanical
trouble in automatic trans-
mission?
EN(H6)-281
S048521B73
Check Yes
Inspect relevant
DTC using "List of
Diagnostic
Trouble Code
(DTC)". <Ref. to
EN(H6)-87, List of
Diagnostic
Trouble Code
(DTC).>
Repair or replace
throttle position
sensor circuit.
Repair or replace
vehicle speed
sensor 2 circuit.
Repair or replace
torque converter
turbine speed
sensor circuit.
Repair poor con-
tact in TCM con-
nector.
Repair or replace
automatic trans-
mission. <Ref. to
AT-12,
INSPECTION,
Road Test.>
Engine (DIAGNOSTICS)
No
Go to step 2.
Go to step 3.
Go to step 4.
Go to step 5.
Go to step 6.
Replace TCM.
<Ref. to AT-49,
Transmission
Control Module
(TCM).>