Subaru LEGACY 2004 Service Manual page 395

Diagnostic Procedure with Diagnostic Trouble Code (DTC)
ENGINE (DIAGNOSTICS)
Step
1 CHECK ANY OTHER DTC ON DISPLAY.
2 CHECK THERMOSTAT.
Check
Is any other DTC displayed?
Does the thermostat remain
opened?
EN(H4SO 2.0)(diag)-106
Yes
Check DTC using Go to step 2.
"List of Diagnostic
Trouble Code
(DTC)". <Ref. to
EN(H4SO
2.0)(diag)-66, List
of Diagnostic Trou-
ble Code (DTC).>
NOTE:
In this case, it is
not necessary to
inspect DTC
P0125.
Replace the ther- Replace the
mostat. <Ref. to engine coolant
CO(H4SO 2.0)-18, temperature sen-
Thermostat.> sor. <Ref. to
FU(H4SO 2.0)-20,
Engine Coolant
Temperature Sen-
sor.>
No