Subaru Impreza 2004 Service Manual page 12

HVAC SYSTEM (AUTO A/C) (DIAGNOSTICS)
Step
5 CHECK MODE DOOR POSITION SIGNAL.
1)Turn the fan speed control dial to 2nd posi-
tion.
2)If the system has trouble for mode door posi-
tion signal, rear window defogger switch LED is
turned off.
3)If the system has no trouble, rear window
defogger switch LED is illuminated.
6 CHECK BLOWER FAN OPERATION.
1)Turn the fan speed control dial to 3rd posi-
tion.
2)Turn the temperature control dial, check that
blower fan speed changes depending on set
temperature.
7 CHECK OPERATION OF EACH ACTUATOR,
BLOWER FAN AND COMPRESSOR
CLUTCH.
1)Turn the fan speed control dial to 4th posi-
tion.
2)Select the operating mode by turning air flow
control dial.
3)Check the operation of each mode according
to operating mode table. <Ref. to AC(diag)-11,
OPERATING MODE TABLE, OPERATION,
Diagnostics Chart for Self-diagnosis.>
•Air inlet
•Air outlet
•Air mix door
•Blower fan
•A/C compressor
Diagnostics Chart for Self-diagnosis
Does the rear window defogger
switch LED illuminate?
Does the blower fan speed
change?
Does the operation of each
mode match to operating mode
table?
AC(diag)-10
Check
Go to step 6.
Go to step 7.
Push the A/C
switch or turn the
ignition switch to
OFF, and finish the
self-diagnosis.
Yes No
Check the mode
door actuator cir-
cuit. <Ref. to
AC(diag)-25,
MODE DOOR
ACTUATOR,
Diagnostic Proce-
dure for Actua-
tors.>
Check the blower
motor circuit. <Ref.
to AC(diag)-14,
BLOWER MOTOR
IS NOT
ROTATED, Diag-
nostics for A/C
System Malfunc-
tion.>
Repair the mal-
function part
according to each
diagnostics chart.