Subaru Impreza 2004 Service Manual page 120

Diagnostic Procedure with Diagnostic Trouble Code (DTC)
Step
1 CHECK ANY OTHER DTC ON DISPLAY.
Check
Is any other DTC displayed?
EN(H4DOTC)(diag)-199
ENGINE (DIAGNOSTICS)
Yes
Inspect the rele- Check the radiator
vant DTC using fan, fan motor, fan
"List of Diagnostic motor connector
Trouble Code and thermostat.
(DTC)". <Ref. to <Ref. to
EN(H4DOTC)(dia CO(H4SO)-23,
g)-74, List of Diag- Radiator Main Fan
nostic Trouble and Fan Motor.>
Code (DTC).> and <Ref. to
CO(H4SO)-24,
Radiator Sub Fan
and Fan Motor.> If
thermostat is
stuck, replace
thermostat.
No