Subaru IMPREZA 2002 Service Manual page 451

DIAGNOSTIC PROCEDURE WITH DIAGNOSTIC TROUBLE CODE (DTC)
ENGINE (DIAGNOSTICS)
Step Check
1
CHECK ANY OTHER DTC ON DISPLAY. Does the Subaru Select Moni-
tor or OBD-II general scan tool
indicate DTC PO1 22 or PO1 23?
Yes
Inspect DTC
PO1 22 or PO1 23
using "List of Diag-
nostic Trouble
Code (DTC)".
<Ref. to
List of Diagnostic
Trouble Code
(DTC).>
NOTE:
In this case, it is
not necessary to
inspect DTC
PO1 21.
EN(S0HC)-77,
No
Replace the throt-
tle position sen-
sor. <Ref. to
Throttle Position
Sensor.>
FU(S0HC)-31,
EN(S0HC)-127