Subaru Impreza 2003 Service Manual page 1416

DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
ENGINE (DIAGNOSTICS)
BY:DTC P0741 — TORQUE CONVERTER CLUTCH CIRCUIT PERFORMANCE
OR STUCK OFF —
• DTC DETECTING CONDITION:
• Two consecutive driving cycles with fault
• TROUBLE SYMPTOM:
• No lock-up (after engine warm-up)
• No shift or excessive tight corner "braking"
CAUTION:
After repair or replacement of faulty parts, conduct Clear Memory Mode <Ref. to EN(H4DOTC)-48, OP-
ERATION, Clear Memory Mode.> and Inspection Mode <Ref. to EN(H4DOTC)-40, Inspection Mode.>.
Step
1 CHECK ANY OTHER DTC ON DISPLAY.
2 CHECK LOCK-UP DUTY SOLENOID CIR-
CUIT.
Check the lock-up duty solenoid circuit. <Ref.
to 4AT-82, DTC 77 LOCK-UP DUTY SOLE-
NOID, Diagnostic Procedure with Diagnostic
Trouble Code (DTC).>
3 CHECK THROTTLE POSITION SENSOR
CIRCUIT.
Check the throttle position sensor circuit. <Ref.
to 4AT-48, DTC 31 THROTTLE POSITION
SENSOR, Diagnostic Procedure with Diagnos-
tic Trouble Code (DTC).>
4 CHECK TORQUE CONVERTER TURBINE
SPEED SENSOR CIRCUIT.
Check the torque converter turbine speed sen-
sor circuit. <Ref. to 4AT-57, DTC 36 TORQUE
CONVERTER TURBINE SPEED SENSOR,
Diagnostic Procedure with Diagnostic Trouble
Code (DTC).>
5 CHECK ENGINE SPEED INPUT CIRCUIT.
Check the engine speed input circuit. <Ref. to
4AT-41, DTC 11 ENGINE SPEED SIGNAL,
Diagnostic Procedure with Diagnostic Trouble
Code (DTC).>
6 CHECK INHIBITOR SWITCH CIRCUIT.
Check the inhibitor switch circuit. <Ref. to 4AT-
109, CHECK INHIBITOR SWITCH, Diagnostic
Procedure without Diagnostic Trouble Code
(DTC).>
7 CHECK BRAKE LIGHT SWITCH CIRCUIT.
Check the brake light switch circuit. <Ref. to
4AT-101, CHECK BRAKE SWITCH, Diagnos-
tic Procedure without Diagnostic Trouble Code
(DTC).>
Check
Is any other DTC displayed?
Is there any trouble in lock-up
duty solenoid circuit?
Is there any trouble in throttle
position sensor circuit?
Is there any trouble in torque
converter turbine speed sensor
circuit?
Is there any trouble in engine
speed input circuit?
Is there any trouble in inhibitor
switch circuit?
Is there any trouble in brake
light switch circuit?
EN(H4DOTC)-240
Yes
Inspect the rele- Go to step 2.
vant DTC using
"List of Diagnostic
Trouble Code
(DTC)". <Ref. to
EN(H4DOTC)-75,
List of Diagnostic
Trouble Code
(DTC).>
Repair or replace Go to step 3.
the lock-up duty
solenoid circuit.
Repair or replace Go to step 4.
the throttle posi-
tion sensor circuit.
Repair or replace Go to step 5.
the torque con-
verter turbine
speed sensor cir-
cuit.
Repair or replace Go to step 6.
the engine speed
input circuit.
Repair or replace Go to step 7.
the inhibitor switch
circuit.
Repair or replace Go to step 8.
the brake light
switch circuit.
No