2009 SUBARU TRIBECA hvac

AC(diag)-31
Diagnostic Procedure for Sensors
HVAC SYSTEM (AUTO A/C) (DIAGNOSTICS)
8. Diagnostic Procedure for Sensors
A: AMBIENT SENSOR
TROUBLE SYMPTOM:
Fan speed is not switched when the fan speed control dial is in AUTO position.
WIRING DIAGRAM:
AC-01341
B283
F78
B1B14
B:
21
F78
12
1011
1413
B26B25
C3C10
F108
B361
B280
B281
B:
C:
5467821931022 23111213141524 25 26 2716171828 29192021 30
B280B:B281
567821943102422 2325111213141526 27281617181920 21
C:
1234567891011121314
B361
123 8910411 12 13 14 15 165671718
F108
AUTO A/CCONTROL MODULE
AMBIENT SENSOR
BODY INTEGRATED UNIT
THROUGH JOINT CONNECTOR
B283B:
1234567891014151617181920212223111213242526

AC(diag)-32
Diagnostic Procedure for Sensors
HVAC SYSTEM (AUTO A/C) (DIAGNOSTICS)
Step Check Yes No
1CHECK 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.
Te r m i n a l s
No. 1 — No. 2:
Is the resistance approximately
1.7 kΩ at 25°C (77°F)?
Go to step 2.Replace the ambi-
ent sensor.
2CHECK 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 (–):
Is the voltage approx. 5 V? Go to step 6.Go to step 3.
3CHECK OUTPUT SIGNAL OF BODY INTE-
GRATED UNIT.
1) Turn the ignition switch to OFF.
2) Draw out the body integrated unit.
3) Disconnect the connector from ambient
sensor.
4) Turn the ignition switch to ON.
5) Measure the voltage between connector
terminals of body integrated unit.
Connector & terminal
(B281) No. 3 (+) — No. 10 (–):
Is the voltage approx. 5 V? Go to step 4.Go to step 6.
4CHECK HARNESS CONNECTOR BETWEEN
BODY INTEGRATED UNIT AND AMBIENT
SENSOR.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from body inte-
grated unit.
3) Measure the resistance of harness
between body integrated unit and ambient sen-
sor.
Connector & terminal
(F78) No. 1 — (B281) No. 10:
Is the resistance less than 1
Ω?
Go to step 5.Repair the open
circuit of harness
between body inte-
grated unit and
ambient sensor.
5CHECK HARNESS CONNECTOR BETWEEN
BODY INTEGRATED UNIT AND AMBIENT
SENSOR.
Measure the resistance of harness between
body integrated unit and ambient sensor.
Connector & terminal
(F78) No. 2 — (B281) No. 3:
Is the resistance less than 1
Ω?
Go to step 6.Repair the open
circuit of harness
between body inte-
grated unit and
ambient sensor.
6CHECK COMMUNICATION ERROR DIS-
PLAY.
1) Connect the connectors of body integrated
unit and ambient sensor as originally con-
nected.
2) Check if “Er xx” is displayed on the Odo/Trip
meter in combination meter after turning the
ignition switch to ON.
Is “Er xx” displayed? Check the commu-
nication circuit.
LAN(diag)-2, Basic
Diagnostic Proce-
dure.>
Go to step 7.
7CHECK POOR CONTACT.
Check poor contact of auto A/C control module
connector.
Is there poor contact in con-
nector?
Repair the con-
nector.
Replace the auto
A/C control mod-
ule. 32, REMOVAL,
Control Unit (Auto
A/C Model).>

AC(diag)-33
Diagnostic Procedure for Sensors
HVAC SYSTEM (AUTO A/C) (DIAGNOSTICS)
B: IN-VEHICLE SENSOR
TROUBLE SYMPTOM:
Blower fan speed, outlet port and inlet port do not change after turning the AUTO switch to ON
WIRING DIAGRAM:
AC-01342
A:B282
12345678910 11 12 13 14 15 16
i55
A:B282
A15A5
21
i55
12
AUTO A/CCONTROL MODULE
IN-VEHICLESENSOR

AC(diag)-34
Diagnostic Procedure for Sensors
HVAC SYSTEM (AUTO A/C) (DIAGNOSTICS)
Step Check Yes No
1CHECK IN-VEHICLE SENSOR.
1) Turn the ignition switch to OFF.
2) Remove the driver’s side lower cover.
3) Disconnect the connector from in-vehicle
sensor.
4) Measure the resistance between connector
terminals of in-vehicle sensor.
Te r m i n a l s
No. 1 — No. 2:
Is the resistance approximately
1.7 kΩ at 20°C (68°F)?
Go to step 2.Replace the in-
vehicle sensor.
2CHECK INPUT SIGNAL FOR IN-VEHICLE
SENSOR.
1) Turn the ignition switch to ON.
2) Measure the voltage between in-vehicle
sensor harness connector terminal and chas-
sis ground.
Connector & terminal
(i55) No. 2 (+) — No. 1 (–):
Is the voltage approx. 5 V? Go to step 6.Go to step 3.
3CHECK AUTO A/C CONTROL MODULE
OUTPUT SIGNAL.
1) Turn the ignition switch to OFF.
2) Remove the auto A/C control module.
3) Turn the ignition switch to ON.
4) Measure the voltage between connector
terminals of auto A/C control module.
Connector & terminal
(B282) No. 5 (+) — (B282) No. 15 (–):
Is the voltage approx. 5 V? Go to step 4.Go to step 6.
4CHECK HARNESS BETWEEN AUTO A/C
CONTROL MODULE AND IN-VEHICLE SEN-
SOR.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from auto A/C
control module.
3) Measure the resistance of harness
between auto A/C control module and in-vehi-
cle sensor.
Connector & terminal
(i55) No. 2 — (B282) No. 5:
Is the resistance less than 1
Ω?
Go to step 5.Repair the har-
ness between auto
A/C control mod-
ule and in-vehicle
sensor.
5CHECK HARNESS BETWEEN AUTO A/C
CONTROL MODULE AND IN-VEHICLE SEN-
SOR.
Measure the resistance of harness between
auto A/C control module and in-vehicle sensor.
Connector & terminal
(i55) No. 1 — (B282) No. 15:
Is the resistance less than 1
Ω?
Go to step 6.Repair the har-
ness between auto
A/C control mod-
ule and in-vehicle
sensor.
6CHECK POOR CONTACT.
Check poor contact of auto A/C control module
connector.
Is there poor contact in con-
nector?
Repair the con-
nector.
Replace the auto
A/C control mod-
ule. 32, REMOVAL,
Control Unit (Auto
A/C Model).>

AC(diag)-35
Diagnostic Procedure for Sensors
HVAC SYSTEM (AUTO A/C) (DIAGNOSTICS)
C: EVAPORATOR SENSOR
WIRING DIAGRAM:
AC-00831
A13A15
B8812
EVAPORATORSENSOR
B88
B282A:AUTO A/CCONTROL MODULE
12123412 891011 12 13 14 15 16567
B282A:

AC(diag)-36
Diagnostic Procedure for Sensors
HVAC SYSTEM (AUTO A/C) (DIAGNOSTICS)
Step Check Yes No
1CHECK EVAPORATOR SENSOR
1) Turn the ignition switch to OFF.
2) Remove the glove box.
3) Disconnect the connector from evaporator
sensor.
4) Measure the resistance between connector
terminals of evaporator sensor.
Te r m i n a l s
No. 1 — No. 2:
Is the resistance approximately
1.9 kΩ at 20°C (68°F)?
Go to step 2.Replace the evap-
orator sensor.
REMOVAL, Evap-
orator.>
2CHECK INPUT SIGNAL FOR EVAPORATOR
SENSOR.
1) Turn the ignition switch to ON.
2) Measure the voltage between connector
(B88) terminal and chassis ground.
Connector & terminal
(B88) No. 1 (+) — No. 2 (–):
Is the voltage approx. 5 V? Go to step 6.Go to step 3.
3CHECK AUTO A/C CONTROL MODULE
OUTPUT SIGNAL.
1) Turn the ignition switch to OFF.
2) Remove the auto A/C control module.
3) Turn the ignition switch to ON.
4) Measure the voltage between connector
terminals of auto A/C control module.
Connector & terminal
(B282) No. 13 (+) — No. 15 (–):
Is the voltage approx. 5 V? Go to step 4.Go to step 6.
4CHECK HARNESS CONNECTOR BETWEEN
AUTO A/C CONTROL MODULE AND EVAP-
ORATOR SENSOR.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from auto A/C
control module.
3) Measure the resistance of harness
between auto A/C control module and evapo-
rator sensor.
Connector & terminal
(B88) No. 2 — (B282) No. 15:
Is the resistance less than 1
Ω?
Go to step 5.Repair the open
circuit of harness
between auto A/C
control module
and evaporator
sensor.
5CHECK HARNESS CONNECTOR BETWEEN
AUTO A/C CONTROL MODULE AND EVAP-
ORATOR SENSOR.
Measure the resistance of harness between
auto A/C control module and evaporator sen-
sor.
Connector & terminal
(B88) No. 1 — (B282) No. 13:
Is the resistance less than 1
Ω?
Go to step 6.Repair the open
circuit of harness
between auto A/C
control module
and evaporator
sensor.
6CHECK POOR CONTACT.
Check poor contact of auto A/C control module
connector.
Is there poor contact in con-
nector?
Repair the con-
nector.
Replace the auto
A/C control mod-
ule. 32, REMOVAL,
Control Unit (Auto
A/C Model).>

AC(diag)-37
Diagnostic Procedure for Sensors
HVAC SYSTEM (AUTO A/C) (DIAGNOSTICS)
D: SUNLOAD SENSOR
TROUBLE SYMPTOM:
•Sensor identifies that sunlight is at maximum. Then, A/C system is controlled to COOL side.
•Sensor identifies that sunlight is at minimum. Then, A/C system is controlled to HOT side.
NOTE:
When the sunload sensor check is performed indoors or in the shade, it could be diagnosed as having an
open circuit. Always check the sunload sensor with the sun shining on it.
WIRING DIAGRAM:
AC-00832
A:B282
12345678910 11 12 13 14 15 16
i51
A:B282
A8A6
21
i3
B38
i51
12
AUTO A/C CONTROL MODULE
32
1234 5678910 11 12 13 14 15 16 17 18 19 20
B38
SUNLOADSENSOR

AC(diag)-38
Diagnostic Procedure for Sensors
HVAC SYSTEM (AUTO A/C) (DIAGNOSTICS)
Step Check Yes No
1CHECK POWER SUPPLY VOLTAGE FOR
SUNLOAD SENSOR.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from sunload
sensor.
3) Turn the ignition switch to ON.
4) Measure the power supply voltage for sun-
load sensor.
Connector & terminal
(i51) No. 1 (+) — No. 2 (–):
Is the voltage approx. 5 V? Go to step 4.Go to step 2.
2CHECK HARNESS CONNECTOR BETWEEN
AUTO A/C CONTROL MODULE AND SUN-
LOAD SENSOR.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from auto A/C
control module.
3) Measure the resistance of harness
between auto A/C control module and sunload
sensor.
Connector & terminal
(i51) No. 2 — (B282) No. 6:
Is the resistance less than 1
Ω?
Go to step 3.Repair the har-
ness between auto
A/C control mod-
ule and sunload
sensor.
3CHECK HARNESS CONNECTOR BETWEEN
AUTO A/C CONTROL MODULE AND SUN-
LOAD SENSOR.
Measure the resistance of harness between
auto A/C control module and sunload sensor.
Connector & terminal
(i51) No. 1 — (B282) No. 8:
Is the resistance less than 1
Ω?
Go to step 4.Repair the har-
ness between auto
A/C control mod-
ule and sunload
sensor.
4CHECK INPUT VOLTAGE FOR AUTO A/C
CONTROL MODULE.
1) Connect the connectors of sunload sensor
and auto A/C control module.
2) Turn the ignition switch to ON.
3) Measure the voltage between connector
terminals of auto A/C control module.
Connector & terminal
(B282) No. 8 (+) — (B282) No. 6 (–):
Is the voltage approx. 3.0 V? Go to step 5.Replace the sun-
load sensor. to AC-44,
REMOVAL, Sun-
load Sensor (Auto
A/C Model).>
5CHECK POOR CONTACT.
Check poor contact of auto A/C control module
connector.
Is there poor contact in con-
nector?
Repair the con-
nector.
Replace the auto
A/C control mod-
ule. 32, REMOVAL,
Control Unit (Auto
A/C Model).>