Subaru Legacy 2003 Service Manual page 2055

DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
ENGINE (DIAGNOSTICS)
BD:DTC P1241 — 2STAGE TWIN TURBO SYSTEM (SINGLE) —
• TROUBLE SYMPTOM:
• Poor driving performance
CAUTION:
After repair or replacement of faulty parts, conduct Clear Memory Mode <Ref. to EN(H4DOSTC)-35,
OPERATION, Clear Memory Mode.> and Inspection Mode <Ref. to EN(H4DOSTC)-33, Inspection
Mode.> .
• WIRING DIAGRAM:
1 CHECK ANY OTHER DTC ON DISPLAY.
Is any other DTC displayed?
2 CHECK OPERATION OF RELIEF VALVE
CONTROL SOLENOID VALVE 2.
Operate the relief valve control solenoid valve
2. <Ref. to EN(H4DOSTC)-36, Compulsory
Valve Operation Check Mode.>
Does the relief valve control solenoid valve 2
produce operating sound?
3 CHECK OPERATION OF EXHAUST CON-
TROL VALVE.
1) Operate the exhaust valve control solenoid
valve. <Ref. to EN(H4DOSTC)-36, Compul-
sory Valve Operation Check Mode.>
2) Check the operation of exhaust control
valve actuator.
Does the actuator rod operate correctly?.
NOTE:
Actuator rod operates in approx. 7 second cy-
cle, and stroke is approx. 30 mm (1.18 in).
4 CHECK OPERATION OF INTAKE AIR CON-
TROL VALVE.
1) Operate the intake air valve control sole-
noid valve. <Ref. to EN(H4DOSTC)-36,
Compulsory Valve Operation Check
Mode.>
2) Check the operation of intake air control
valve actuator.
Does the actuator rod operate correctly?
NOTE:
Actuator rod operates in approx. 2 second cy-
cle, and stroke is approx. 12 mm (0.47 in).
5 CHECK RELIEF VALVE.
1) Remove the relief valve.
2) Check the relief valve.
Is there a fault in the relief valve and hose
routing?
6 CHECK VACUUM HOSES OF EXHAUST
VALVE CONTROL SOLENOID VALVE (POS-
ITIVE PRESSURE).
Are there cracks, stuck or improper routing on
vacuum hose?
Step
EN(H4DOSTC)-216
Value
DTC indicated.
Operating sound produced.
Operates correctly.
Operates correctly.
There is no problem.
There is no problem.
Yes
Inspect the rele- Go to step 2.
vant DTC using
"List of Diagnostic
Trouble Code
(DTC)". <Ref. to
EN(H4DOSTC)-
62, List of Diag-
nostic Trouble
Code (DTC).>
Go to step 3. Replace the relief
valve control sole-
noid valve 2. <Ref.
to IN(H4DOSTC)-
19, Solenoid Box
Assembly.>
Go to step 4. Check the exhaust
valve control sole-
noid valve and
vacuum hose.
<Ref. to
IN(H4DOSTC)-19,
Solenoid Box
Assembly.>
Go to step 5. Check the intake
air control solenoid
valve and vacuum
hose. <Ref. to
IN(H4DOSTC)-19,
Solenoid Box
Assembly.>
Go to step 6. Replace or repair
the relief valve and
vacuum hose.
Go to step 7. Repair or replace
the vacuum hoses.
No