Subaru Legacy 2005 Service Manual page 1390

Diagnostic Procedure with Diagnostic Trouble Code (DTC)
ENGINE (DIAGNOSTICS)
Step
1 CHECK HARNESS BETWEEN IGNITION
SWITCH AND ECM.
1) Disconnect the connector from ECM.
2) Measure the voltage between ECM and
chassis ground.
Connector & terminal
(B137) No. 32 (+) — Chassis ground (
AQ:DTC P0519 IDLE AIR CONTROL SYSTEM PERFORMANCE
DTC DETECTING CONDITION:
Immediately at fault recognition
TROUBLE SYMPTOM:
• Engine keeps running at higher speed than specified idle speed.
• Fuel is cut according to fail-safe function.
CAUTION:
After repair or replacement of faulty parts, perform Clear Memory Mode <Ref. to EN(H4DOTC)(diag)-
37, OPERATION, Clear Memory Mode.> and Inspection Mode <Ref. to EN(H4DOTC)(diag)-30, PROCE-
DURE, Inspection Mode.>.
Step
1 CHECK ANY OTHER DTC ON DISPLAY.
2 CHECK AIR INTAKE SYSTEM.
1) Turn the ignition switch to ON.
2) Start and idle the engine.
3) Check the following items.
• Loose installation of intake manifold and
throttle body
• Cracks of intake manifold gasket and throttle
body gasket
• Disconnections of vacuum hoses
3 CHECK ELECTRONIC THROTTLE CON-
TROL.
1) Turn the ignition switch to OFF.
2) Remove the electronic throttle control.
3) Check the electronic throttle control.
Check
Is the voltage more than 10 V? Repair the battery
−
):
Check
Is any other DTC displayed?
Is there any fault in air intake
system?
Are foreign matters found
inside the electronic throttle
control?
EN(H4DOTC)(diag)-150
Yes
Repair the poor
short circuit of har- contact in ECM.
ness between igni-
tion switch and
ECM.
Yes
Inspect the rele- Go to step 2.
vant DTC using
"List of Diagnostic
Trouble Code
(DTC)". <Ref. to
EN(H4DOTC)(diag
)-62, List of Diag-
nostic Trouble
Code (DTC).>
NOTE:
In this case, it is
not necessary to
inspect DTC
P0519.
Repair air suction Go to step 3.
and leaks.
Remove foreign Perform the diag-
matters from the nosis of DTC
electronic throttle P2101.
control.
No
No