Subaru 2009 IMPREZA Service Manual page 1352

Diagnostic Procedure with Diagnostic Trouble Code (DTC)
W: DTC P0125 INSUFFICIENT COOLANT TEMPERATURE FOR CLOSED LOOP
FUEL CONTROL
DTC DETECTING CONDITION:
• Detected when two consecutive driving cycles with fault occur.
• GENERAL DESCRIPTION <Ref. to GD(H4DOTC)-40, DTC P0125 INSUFFICIENT COOLANT TEMPER-
ATURE FOR CLOSED LOOP FUEL CONTROL, Diagnostic Trouble Code (DTC) Detecting Criteria.>
TROUBLE SYMPTOM:
Engine does not return to idle.
CAUTION:
After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(H4DOTC)(diag)-54,
OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(H4DOTC)(diag)-43, PROCE-
DURE, Inspection Mode.>.
Step
1 CHECK TIRE SIZE.
2 CHECK ENGINE COOLANT.
Check the following items:
• Amount of engine coolant
• Engine coolant freeze
• Contamination of engine coolant
3 CHECK THERMOSTAT.
Check
Is the tire size as specified and
the same size as three other
wheels?
Is the engine coolant normal?
Does the thermostat remain
opened?
EN(H4DOTC)(diag)-131
ENGINE (DIAGNOSTICS)
Yes No
Go to step 2. Replace the tire.
Go to step 3. Fill or replace the
engine coolant.
<Ref. to
CO(H4DOTC)-14,
REPLACEMENT,
Engine Coolant.>
Replace the ther- Replace the
mostat. <Ref. to engine coolant
CO(H4DOTC)-18, temperature sen-
Thermostat.> sor. <Ref. to
FU(H4DOTC)-31,
Engine Coolant
Temperature Sen-
sor.>