Subaru Legacy 2004 Service Manual page 3439

Step
1 CHECK POWER SUPPLY FOR MODE DOOR
ACTUATOR POSITION SENSOR.
1) Turn the ignition switch to OFF.
2) Disconnect the mode door actuator con-
nector.
3) Turn the ignition switch and AUTO switch to
ON.
4) Measure the voltage between auto A/C
control module connector terminals.
Connector & terminal
(B282) No. 8 (+) — (B282) No. 15 (
2 CHECK POWER SUPPLY FOR MODE DOOR
ACTUATOR.
Measure the voltage between auto A/C control
module connector and chassis ground after
turning the air flow control switch to FACE posi-
tion.
Connector & terminal
(B283) No. 7 (+) — Chassis ground (
3 CHECK POWER SUPPLY FOR MODE DOOR
ACTUATOR.
Measure the voltage between auto A/C control
module connector and chassis ground after
turning the air flow control switch to DEF posi-
tion.
Connector & terminal
(B283) No. 17 (+) — Chassis ground (
4 CHECK HARNESS BETWEEN AUTO A/C
CONTROL MODULE AND MODE DOOR AC-
TUATOR.
1) Turn the A/C and ignition switch to OFF.
2) Disconnect the auto A/C control module
connector.
3) Measure the resistance between auto A/C
control module and mode door actuator con-
nector.
Connector & terminal
(B77) No. 1 — (B282) No. 15:
(B77) No. 2 — (B282) No. 8:
(B77) No. 3 — (B282) No. 3:
(B77) No. 4 — (B283) No. 17:
(B77) No. 5 — (B283) No. 7:
5 CHECK MODE DOOR ACTUATOR POSI-
TION SWITCH SIGNAL.
1) Connect the connector of auto A/C control
module and mode door actuator.
2) Turn the ignition switch and AUTO switch to
ON.
3) Check the voltage between auto A/C con-
trol module connector terminals while chang-
ing the mode between DEF and FACE.
Connector & terminal
(B282) No. 3 (+) — (B282) No. 15 (
6 CHECK POOR CONTACT.
Check poor contact in auto A/C control module
and connector.
Diagnostic Procedure for Actuators
Is the voltage approx. 5 V?
$
):
Is the voltage 7 V (at normal
temperature)?
$
):
Is the voltage 7 V (at normal
temperature)?
$
):
Is the resistance less than 1
#?
Does the voltage change
between 1 (DEF) — 4 (FACE)
V?
$
):
Is there poor contact in con-
nector?
AC(diag)-27
HVAC SYSTEM (AUTO A/C) (DIAGNOSTICS)
Check Yes
Go to step 2.
Go to step 3.
Go to step 4.
Go to step 5.
Go to step 6.
Repair connector. Replace the auto
No
Replace the auto
A/C control mod-
ule.
Replace the auto
A/C control mod-
ule.
Replace the auto
A/C control mod-
ule.
Repair the har-
ness between auto
A/C control mod-
ule and mode door
actuator.
Replace the mode
door actuator.
A/C control mod-
ule.