Subaru Legacy 2002 Service Manual page 3182

DIAGNOSTICS FOR A/C SYSTEM FAILURE (LHD MODEL)
No.
1 CHECK SWITCH OPERATION.
Make sure that the mode selection on display
is changed when pushing the "MODE" switch.
2 CHECK FUSE.
1) Remove No. 17 fuse in joint box.
2) Check condition of fuse.
3 CHECK SIGNAL VOLTAGE.
1) Change display to RECIRC by pushing
MODE switch.
2) Measure voltage between A/C control mod-
ule and chassis ground.
Connector & terminal
(i48) No. 15 (+) — Chassis ground (−):
4 CHECK SIGNAL VOLTAGE.
1) Change display to FRESH with pushing
MODE switch.
2) Measure voltage between A/C control mod-
ule and chassis ground.
Connector & terminal
(i48) No. 7 (+) — Chassis ground (−):
5 CHECK HARNESS CONNECTOR
BETWEEN A/C CONTROL MODULE AND
FRESH/RECIRC ACTUATOR.
1) Turn ignition switch to OFF.
2) Disconnect connector from A/C control
module and mode door motor.
3) Measure resistance of harness between
A/C control module and FRESH/RECIRC
actuator.
Connector & terminal:
(i48) No. 15 — (B91) No. 1
6 CHECK HARNESS CONNECTOR
BETWEEN A/C CONTROL MODULE AND
FRESH/RECIRC ACTUATOR.
Measure resistance of harness between A/C
control module and FRESH/RECIRC actuator.
Connector & terminal:
(i48) No. 7 — (B91) No. 2
7 CHECK POOR CONTACT.
Check poor contact in A/C control module.
Step
Does the mode selection
change?
Is the fuse blown-out?
Is the voltage less than 1
V?
Is the voltage less than 1
V?
Is the resistance less than
1 Ω?
Is the resistance less than
1 Ω?
Is there poor contact in A/C
control module?
AC-39
HVAC System (Auto A/C) (Diagnostics)
Check Yes
Go to step 7.
Replace fuse.
Go to step 4.
Go to step 5.
Go to step 6.
Go to step 7.
Repair poor con-
tact in A/C control
module.
No
Go to step 2.
Go to step 3.
Repair short cir-
cuit in harness for
power supply line.
Repair short cir-
cuit in harness for
power supply line.
Repair open cir-
cuit in harness
between A/C con-
trol module and
FRESH/RECIRC
actuator.
Repair open cir-
cuit in harness
between A/C con-
trol module and
FRESH/RECIRC
actuator.
Contact with your
Subaru distributor
service.