Subaru 2002 IMPREZA Service Manual page 1413

DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
BO:DTC P0734 — GEAR 4 INCORRECT RATIO —
• DTC DETECTING CONDITION:
• Two consecutive driving cycles with fault
• TROUBLE SYMPTOM:
• Shift point too high or too low; engine brake not effective in "3" range; excessive shift shock; excessive
tight corner "braking"
CAUTION:
After repair or replacement of faulty parts, conduct Clear Memory Mode <Ref. to EN(TURBO)-45, OP-
ERATION, Clear Memory Mode.> and Inspection Mode <Ref. to EN(TURBO)-42, Inspection Mode.>.
• WIRING DIAGRAM:
Step
1 CHECK ANY OTHER DIAGNOSTIC TROU-
BLE CODE (DTC) ON DISPLAY.
2 CHECK THROTTLE POSITION SENSOR
CIRCUIT.
Check the throttle position sensor circuit. <Ref.
to AT-50, DTC 31 THROTTLE POSITION
SENSOR, Diagnostic Procedure with Diagnos-
tic Trouble Code (DTC).>
3 CHECK FRONT VEHICLE SPEED SENSOR
CIRCUIT.
Check the front vehicle speed sensor circuit.
<Ref. to AT-57, DTC 33 FRONT VEHICLE
SPEED SENSOR, Diagnostic Procedure with
Diagnostic Trouble Code (DTC).>
4 CHECK TORQUE CONVERTER TURBINE
SPEED SENSOR CIRCUIT.
Check the torque converter turbine speed sen-
sor circuit. <Ref. to AT-62, 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.
Check
Is any other DTC displayed?
Is there any trouble in throttle
position sensor circuit?
Is there any trouble in vehicle
speed sensor 2 circuit?
Is there any trouble in torque
converter turbine speed sensor
circuit?
Is there poor contact in TCM
connector?
Is there any mechanical trou-
ble in automatic transmission?
EN(TURBO)-253
ENGINE (DIAGNOSTICS)
Yes
Inspect the rele- Go to step 2.
vant DTC using
"List of Diagnostic
Trouble Code
(DTC)". <Ref. to
EN(TURBO)-75,
List of Diagnostic
Trouble Code
(DTC).>
Repair or replace Go to step 3.
the throttle posi-
tion sensor circuit.
Repair or replace Go to step 4.
the vehicle speed
sensor 2 circuit.
Repair or replace Go to step 5.
the torque con-
verter turbine
speed sensor cir-
cuit.
Repair the poor Go to step 6.
contact in TCM
connector.
Repair or replace Replace the TCM.
the automatic <Ref. to AT-46,
transmission. Transmission Con-
<Ref. to AT-12, trol Module
INSPECTION, (TCM).>
Road Test.>
No