Subaru Impreza 2004 Service Manual page 13

1. SENSOR CHECK TABLE
NOTE:
When the sunload sensor is checked indoors or in the shade, open circuit might be indicated. Always check
the sunload sensor at a place where sun shines directly on it.
Air flow control
dial position
VENT
BI-LEVEL
HEAT Evaporator sensor
DEF/HEAT
Air mix door motor (Potentio
DEF
2. OPERATING MODE TABLE
Operation
Air outlet
Air inlet RECIRC
Air mix door FULL COOL
Blower fan
A/C compressor
Diagnostics Chart for Self-diagnosis
Checked sensor
A/C switch LED and FRESH/
Ambient sensor RECIRC switch LED illumi-
A/C switch LED and FRESH/
In-vehicle sensor RECIRC switch LED illumi-
A/C switch LED and FRESH/
RECIRC switch LED illumi-
A/C switch LED and FRESH/
Sunload sensor RECIRC switch LED illumi-
A/C switch LED and FRESH/
RECIRC switch LED illumi-
balance resistor)
VENT BI-LEVEL
VENT BI-LEVEL
RECIRC
FULL COOL
5V 5V
ON OFF
HVAC SYSTEM (AUTO A/C) (DIAGNOSTICS)
No trouble
nate
nate
nate
nate
nate
Air flow control dial position
HEAT
HEAT
RECIRC
FULL HOT
8V
OFF
AC(diag)-11
Short circuit
A/C switch LED illu- FRESH/RECIRC
minate switch LED illuminate
A/C switch LED illu- FRESH/RECIRC
minate switch LED illuminate
A/C switch LED illu- FRESH/RECIRC
minate switch LED illuminate
A/C switch LED illu- FRESH/RECIRC
minate switch LED illuminate
A/C switch LED illuminate
DEF/HEAT
DEF/HEAT
FRESH
FULL HOT
Power supply
10V
ON
Open circuit
DEF
DEF
FRESH
FULL COOL
voltage
ON