Subaru Legacy 2005 Service Manual page 3523

Step
1 CHECK AMBIENT SENSOR.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from ambient
sensor.
3) Measure the resistance between connector
terminals of ambient sensor.
Terminals
No. 1 — No. 2:
2 CHECK INPUT SIGNAL FOR AMBIENT SEN-
SOR.
1) Turn the ignition to ON.
2) Measure the voltage between connector
(F78) terminals.
Connector & terminal
(F78) No. 1 (+) — No. 2 (
3 CHECK OUTPUT SIGNAL OF BODY INTE-
GRATED MODULE.
1) Turn the ignition switch to OFF.
2) Draw out the body integrated module.
3) Disconnect the connector from ambient
sensor.
4) Turn the ignition switch to ON.
5) Measure the voltage between connector
terminals of body integrated module.
Connector & terminal
(B281) No. 3 (+) — No. 10 (
4 CHECK HARNESS CONNECTOR BETWEEN
BODY INTEGRATED MODULE AND AMBI-
ENT SENSOR.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from body inte-
grated module.
3) Measure the resistance in harness
between body integrated module and ambient
sensor.
Connector & terminal
(F78) No. 1 — (B281) No. 10:
5 CHECK HARNESS CONNECTOR BETWEEN
BODY INTEGRATED MODULE AND AMBI-
ENT SENSOR.
Measure the resistance in harness between
body integrated module and ambient sensor.
Connector & terminal
(F78) No. 2 — (B281) No. 3:
6 CHECK COMMUNICATION ERROR DIS-
PLAY.
1) Connect the connectors of body integrated
module and ambient sensor.
2) Check "Er lu" is indicated on the Odo/Trip
meter in combination meter after turning the
ignition switch to ON.
Diagnostic Procedure for Sensors
Is the resistance approx. 2.2
kΩ at 25°C (77°F)?
Is the voltage approx. 5 V?
−
):
Is the voltage approx. 5 V?
−
):
Is the resistance less than 1
Ω?
Is the resistance less than 1
Ω?
Is the error display "Er lu" indi-
cated?
AC(diag)-31
HVAC SYSTEM (AUTO A/C) (DIAGNOSTICS)
Check
Go to step 2.
Go to step 6.
Go to step 4.
Go to step 5.
Go to step 6.
Replace the body
integrated mod-
ule. <Ref. to SL-
44, REMOVAL,
Body Integrated
Module.>
Yes No
Replace the ambi-
ent sensor.
Go to step 3.
Go to step 6.
Repair the open
circuit in harness
between body inte-
grated module and
ambient sensor.
Repair the open
circuit in harness
between body inte-
grated module and
ambient sensor.
Go to step 7.