2004 SUBARU FORESTER ignition

4AT(H4DOTC)-37
AUTOMATIC TRANSMISSION (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
31 CHECK INPUT SIGNAL FOR TCM.
1) Move the select lever except for “R” range.
2) Measure the voltage between TCM and
chassis ground.
Connector & terminal
(B55) No. 14 (+) — Chassis ground (–):Is the voltage more than 8 V? Go to step 65.Replace the TCM.
Transmission Con-
trol Module
(TCM).>
32 CHECK “R” RANGE INDICATOR LIGHT
BULB.
1) Turn the ignition switch to OFF.
2) Remove the combination meter.
3) Remove the “R” range indicator light bulb
from combination meter.Is “R” range indicator light bulb
OK?Go to step 33.Replace the “R”
range indicator light
bulb. 10, Combination
Meter Assembly.>
33 CHECK HARNESS CONNECTOR BETWEEN
TCM AND COMBINATION METER.
1) Disconnect the connectors from TCM and
combination meter.
2) Measure the resistance of harness
between TCM and combination meter.
Connector & terminal
(B55) No. 14 — (i12) No. 13:Is the resistance less than 1
Ω?Go to step 65.Repair the open
circuit in harness
between TCM con-
nector and combi-
nation meter, and
poor contact in
TCM connector.
34 CHECK HARNESS CONNECTOR BETWEEN
TCM AND INHIBITOR SWITCH.
1) Turn the ignition switch to OFF.
2) Disconnect the connectors from TCM,
inhibitor switch and combination meter.
3) Measure the resistance of harness
between TCM and chassis ground.
Connector & terminal
(B55) No. 14 — Chassis ground:Is the resistance more than 1
MΩ?Go to step 35.Repair the ground
short circuit in “R”
range circuit.
35 CHECK HARNESS CONNECTOR BETWEEN
TCM AND INHIBITOR SWITCH.
1) Turn the ignition switch to OFF.
2) Disconnect the connectors from TCM and
inhibitor switch.
3) Measure the resistance of harness
between TCM and inhibitor switch connector.
Connector & terminal
(B55) No. 22 — (T7) No. 10:Is the resistance less than 1
Ω?Go to step 36.Repair the open cir-
cuit in harness
between TCM and
inhibitor switch con-
nector, and poor
contact in coupling
connector.
36 CHECK INPUT SIGNAL FOR TCM.
1) Turn the ignition switch to OFF.
2) Connect the connector to TCM and inhibitor
switch.
3) Turn the ignition switch to ON.
4) Shift the select lever to “N” range.
5) Measure the voltage between TCM and
chassis ground.
Connector & terminal
(B55) No. 22 (+) — Chassis ground (–):Is the voltage less than 1 V? Go to step 37.Go to step 65.
37 CHECK INPUT SIGNAL FOR TCM.
1) Shift the select lever to except for “N”
range.
2) Measure the voltage between TCM and
chassis ground.
Connector & terminal
(B55) No. 22 (+) — Chassis ground (–):Is the voltage more than 8 V? Go to step 65.Replace the TCM.
Transmission Con-
trol Module
(TCM).> Step Check Yes No

4AT(H4DOTC)-38
AUTOMATIC TRANSMISSION (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
38 CHECK “N” RANGE INDICATOR LIGHT
BULB.
1) Turn the ignition switch to OFF.
2) Remove the combination meter.
3) Remove the “N” range indicator light bulb
from combination meter.Is the “N” range indicator light
bulb OK?Go to step 39.Replace the “N”
range indicator light
bulb. 10, Combination
Meter Assembly.>
39 CHECK HARNESS CONNECTOR BETWEEN
TCM AND COMBINATION METER.
1) Disconnect the connectors from TCM and
combination meter.
2) Measure the resistance of harness
between TCM and combination meter.
Connector & terminal
(B55) No. 22 — (i12) No. 12:Is the resistance less than 1
Ω?Go to step 65.Repair the open
circuit in harness
between TCM con-
nector and combi-
nation meter, and
poor contact in
TCM connector.
40 CHECK HARNESS CONNECTOR BETWEEN
TCM AND INHIBITOR SWITCH.
1) Turn the ignition switch to OFF.
2) Disconnect the connectors from TCM,
inhibitor switch and combination meter.
3) Measure the resistance of harness
between TCM connector and chassis ground.
Connector & terminal
(B55) No. 22 — Chassis ground:Is the resistance more than 1
MΩ?Go to step 41.Repair the ground
short circuit in “N”
range circuit.
41 CHECK HARNESS CONNECTOR BETWEEN
TCM AND INHIBITOR SWITCH.
1) Turn the ignition switch to OFF.
2) Disconnect the connectors from TCM and
inhibitor switch.
3) Measure the resistance of harness
between TCM and inhibitor switch connector.
Connector & terminal
(B55) No. 4 — (T7) No. 3:Is the resistance less than 1
Ω?Go to step 42.Repair the open cir-
cuit in harness
between TCM and
inhibitor switch con-
nector, and poor
contact in coupling
connector.
42 CHECK INPUT SIGNAL FOR TCM.
1) Turn the ignition switch to OFF.
2) Connect the connector to TCM and inhibitor
switch.
3) Turn the ignition switch to ON.
4) Shift the select lever to “D” range.
5) Measure the voltage between TCM and
chassis ground.
Connector & terminal
(B55) No. 4 (+) — Chassis ground (–):Is the voltage less than 1 V? Go to step 43.Go to step 65.
43 CHECK INPUT SIGNAL FOR TCM.
1) Shift the select lever except for “D” range.
2) Measure the voltage between TCM and
chassis ground.
Connector & terminal
(B55) No. 4 (+) — Chassis ground (–):Is the voltage more than 8 V? Go to step 65.Replace the TCM.
Transmission Con-
trol Module
(TCM).>
44 CHECK “D” RANGE INDICATOR LIGHT
BULB.
1) Turn the ignition switch to OFF.
2) Remove the combination meter.
3) Remove the “D” range indicator light bulb
from combination meter.Is the “D” range indicator light
bulb OK?Go to step 45.Replace the “D”
range indicator light
bulb. 10, Combination
Meter Assembly.> Step Check Yes No

4AT(H4DOTC)-39
AUTOMATIC TRANSMISSION (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
45 CHECK HARNESS CONNECTOR BETWEEN
TCM AND COMBINATION METER.
1) Disconnect the connectors from TCM and
combination meter.
2) Measure the resistance of harness
between TCM and combination meter.
Connector & terminal
(B55) No. 4 — (i12) No. 11:Is the resistance less than 1
Ω?Go to step 65.Repair the open
circuit in harness
between TCM con-
nector and combi-
nation meter.
46 CHECK HARNESS CONNECTOR BETWEEN
TCM AND INHIBITOR SWITCH.
1) Turn the ignition switch to OFF.
2) Disconnect the connectors from TCM,
inhibitor switch and combination meter.
3) Measure the resistance of harness
between TCM and chassis ground.
Connector & terminal
(B55) No. 4 — Chassis ground:Is the resistance more than 1
MΩ?Go to step 47.Repair the ground
short circuit in “D”
range circuit.
47 CHECK HARNESS CONNECTOR BETWEEN
TCM AND INHIBITOR SWITCH.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from TCM and
inhibitor switch.
3) Measure the resistance of harness
between TCM and inhibitor switch connector.
Connector & terminal
(B54) No. 16 — (T7) No. 11:Is the resistance less than 1
Ω?Go to step 48.Repair the open cir-
cuit in harness
between TCM and
inhibitor switch con-
nector, and poor
contact in coupling
connector.
48 CHECK INPUT SIGNAL FOR TCM.
1) Turn the ignition switch to OFF.
2) Connect the connector to TCM and inhibitor
switch.
3) Turn the ignition switch to ON.
4) Shift the select lever to “3” range.
5) Measure the voltage between TCM and
chassis ground.
Connector & terminal
(B54) No. 16 (+) — Chassis ground (–):Is the voltage less than 1 V? Go to step 49.Go to step 65.
49 CHECK INPUT SIGNAL FOR TCM.
1) Shift the select lever except for “3” range.
2) Measure the voltage between TCM and
chassis ground.
Connector & terminal
(B54) No. 16 (+) — Chassis ground (–):Is the voltage more than 8 V? Go to step 65.Replace the TCM.
Transmission Con-
trol Module
(TCM).>
50 CHECK “3” RANGE INDICATOR LIGHT
BULB.
1) Turn the ignition switch to OFF.
2) Remove the combination meter.
3) Remove the “3” range indicator light bulb
from combination meter.Is the “3” range indicator light
bulb OK?Go to step 51.Replace the “3”
range indicator light
bulb. 10, Combination
Meter Assembly.>
51 CHECK HARNESS CONNECTOR BETWEEN
TCM AND COMBINATION METER.
1) Disconnect the connectors from TCM and
combination meter.
2) Measure the resistance of harness
between TCM and combination meter.
Connector & terminal
(B54) No. 16 — (i12) No. 10:Is the resistance more than 1
Ω?Go to step 65.Repair the open
circuit in harness
between TCM con-
nector and combi-
nation meter, and
poor contact in
TCM connector. Step Check Yes No

4AT(H4DOTC)-40
AUTOMATIC TRANSMISSION (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
52 CHECK HARNESS CONNECTOR BETWEEN
TCM AND INHIBITOR SWITCH.
1) Turn the ignition switch to OFF.
2) Disconnect the connectors from TCM,
inhibitor switch and combination meter.
3) Measure the resistance of harness
between TCM connector and chassis ground.
Connector & terminal
(B54) No. 16 — Chassis ground:Is the resistance more than 1
MΩ?Go to step 53.Repair the ground
short circuit in “3”
range circuit.
53 CHECK HARNESS CONNECTOR BETWEEN
TCM AND INHIBITOR SWITCH.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from TCM and
inhibitor switch.
3) Measure the resistance of harness
between TCM and inhibitor switch connector.
Connector & terminal
(B54) No. 4 — (T7) No. 4:Is the resistance less than 1
Ω?Go to step 54.Repair the open cir-
cuit in harness
between TCM and
inhibitor switch con-
nector, and poor
contact in coupling
connector.
54 CHECK INPUT SIGNAL FOR TCM.
1) Turn the ignition switch to OFF.
2) Connect the connector to TCM and inhibitor
switch.
3) Turn the ignition switch to ON.
4) Shift the select lever to “2” range.
5) Measure the voltage between TCM and
chassis ground.
Connector & terminal
(B54) No. 4 (+) — Chassis ground (–):Is the voltage less than 1 V? Go to step 55.Go to step 65.
55 CHECK INPUT SIGNAL FOR TCM.
1) Shift the select lever except for “2” range.
2) Measure the voltage between TCM and
chassis ground.
Connector & terminal
(B54) No. 4 (+) — Chassis ground (–):Is the voltage more than 8 V? Go to step 65.Replace the TCM.
Transmission Con-
trol Module
(TCM).>
56 CHECK “2” RANGE INDICATOR LIGHT
BULB.
1) Turn the ignition switch to OFF.
2) Remove the combination meter.
3) Remove the “2” range indicator light bulb
from combination meter.Is the “2” range indicator light
bulb OK?Go to step 57.Replace the “2”
range indicator light
bulb. 10, Combination
Meter Assembly.>
57 CHECK HARNESS CONNECTOR BETWEEN
TCM AND COMBINATION METER.
1) Disconnect the connectors from TCM and
combination meter.
2) Measure the resistance of harness
between TCM and combination meter.
Connector & terminal
(B54) No. 4 — (i12) No. 4:Is the resistance less than 1
Ω?Go to step 65.Repair the open
circuit in harness
between TCM and
combination
meter, and poor
contact in TCM
connector.
58 CHECK HARNESS CONNECTOR BETWEEN
TCM AND INHIBITOR SWITCH.
1) Turn the ignition switch to OFF.
2) Disconnect the connectors from TCM,
inhibitor switch and combination meter.
3) Measure the resistance of harness
between TCM and chassis ground.
Connector & terminal
(B54) No. 4 — Chassis ground:Is the resistance more than 1
MΩ?Go to step 59.Repair the ground
short circuit in “2”
range circuit. Step Check Yes No

4AT(H4DOTC)-41
AUTOMATIC TRANSMISSION (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
59 CHECK HARNESS CONNECTOR BETWEEN
TCM AND INHIBITOR SWITCH.
1) Turn the ignition switch to OFF.
2) Disconnect the connectors from TCM and
inhibitor switch.
3) Measure the resistance of harness
between TCM and inhibitor switch connector.
Connector & terminal
(B54) No. 10 — (T7) No. 6:Is the resistance less than 1
Ω?Go to step 60.Repair the open cir-
cuit in harness
between TCM and
inhibitor switch con-
nector, and poor
contact in coupling
connector.
60 CHECK INPUT SIGNAL FOR TCM.
1) Turn the ignition switch to OFF.
2) Connect the connector to TCM and inhibitor
switch.
3) Turn the ignition switch to ON.
4) Shift the select lever to “1” range.
5) Measure the voltage between TCM and
chassis ground.
Connector & terminal
(B54) No. 10 (+) — Chassis ground (–):Is the voltage less than 1 V? Go to step 61.Go to step 65.
61 CHECK INPUT SIGNAL FOR TCM.
1) Shift the select lever except for “1” range.
2) Measure the voltage between TCM and
chassis ground.
Connector & terminal
(B54) No. 10 (+) — Chassis ground (–):Is the voltage more than 8 V? Go to step 65.Replace the TCM.
Transmission Con-
trol Module
(TCM).>
62 CHECK “1” RANGE INDICATOR LIGHT
BULB.
1) Turn the ignition switch to OFF.
2) Remove the combination meter.
3) Remove the “1” range indicator light bulb
from combination meter.Is the “1” range indicator light
bulb OK?Go to step 63.Replace the “1”
range indicator light
bulb. 10, Combination
Meter Assembly.>
63 CHECK HARNESS CONNECTOR BETWEEN
TCM AND COMBINATION METER.
1) Disconnect the connectors from TCM and
combination meter.
2) Measure the resistance of harness
between TCM and combination meter.
Connector & terminal
(B54) No. 10 — (i12) No. 5:Is the resistance less than 1Ω? Go to step 65.Repair the open
circuit in harness
between TCM and
combination meter,
poor contact in
TCM connector.
64 CHECK HARNESS CONNECTOR BETWEEN
TCM AND INHIBITOR SWITCH.
1) Turn the ignition switch to OFF.
2) Disconnect the connectors from TCM,
inhibitor switch and combination meter.
3) Measure the resistance of harness
between TCM connector and chassis ground.
Connector & terminal
(B54) No. 10 — Chassis ground:Is the resistance more than 1
MΩ?Go to step 65.Repair the ground
short circuit in “1”
range circuit.
65 CHECK POOR CONTACT.Is there poor contact in inhibi-
tor switch circuit?Repair the poor
contact.Go to step 66.
66 CHECK INHIBITOR SWITCH.Is the inhibitor switch in proper
position?Replace the TCM.
Transmission Con-
trol Module
(TCM).>Adjust the inhibi-
tor switch and
select cable. to 4AT-51, Inhibi-
tor Switch.> and
Select Cable.> Step Check Yes No

4AT(H4DOTC)-42
AUTOMATIC TRANSMISSION (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
B: DTC P0712 TRANSMISSION FLUID TEMPERATURE SENSOR CIRCUIT LOW
INPUT
DTC DETECTING CONDITION:
Input signal circuit of TCM to ATF temperature sensor is open or shorted.
TROUBLE SYMPTOM:
Excessive shift shock.
WIRING DIAGRAM:
Step Check Yes No
1 CHECK HARNESS CONNECTOR BETWEEN
TCM AND ATF TEMPERATURE SENSOR.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from transmis-
sion and TCM.
3) Measure the resistance of harness
between TCM and transmission connector.
Connector & terminal
(B55) No. 21 — (B11) No. 11:Is the resistance less than 1
Ω?Go to step 2.Repair the open
circuit in harness
between TCM and
transmission con-
nector.
AT-01113
B11
B55
AT11
1
234
56
78
9
1314
15
20
19 1716 10 1112
1821
9
15 11 1
3
B55
B11
AT11
T4 TCM
3412
12 7
8956 34
10 11 12
19 20 2113 14 15 16
17 18 22 23 24
ATF TEMPERATURE
SENSOR
TRANSMISSION

4AT(H4DOTC)-43
AUTOMATIC TRANSMISSION (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
2 CHECK HARNESS CONNECTOR BETWEEN
TCM AND ATF TEMPERATURE SENSOR.
Measure the resistance of harness between
TCM and transmission connector.
Connector & terminal
(B55) No. 9 — (B11) No. 15:Is the resistance less than 1
Ω?Go to step 3.Repair the open
circuit in harness
between TCM and
transmission con-
nector.
3 CHECK HARNESS CONNECTOR BETWEEN
TCM AND ATF TEMPERATURE SENSOR.
Measure the resistance of harness between
TCM connector and chassis ground.
Connector & terminal
(B55) No. 21 — Chassis ground:Is the resistance more than 1
MΩ?Go to step 4.Repair the short
circuit in harness
between TCM and
transmission con-
nector.
4 CHECK HARNESS CONNECTOR BETWEEN
TCM AND ATF TEMPERATURE SENSOR.
Measure the resistance of harness between
TCM connector and chassis ground.
Connector & terminal
(B55) No. 9 — Chassis ground:Is the resistance more than 1
MΩ?Go to step 5.Repair the short
circuit in harness
between TCM and
transmission con-
nector.
5 CHECK ATF TEMPERATURE SENSOR.
1) Turn the ignition switch to OFF.
2) Connect the connectors to transmission
and TCM.
3) Turn the ignition switch to ON and start
engine.
4) Warm-up the transmission until ATF tem-
perature reaches to 80°C (176°F).
N
OTE:
If ambient temperature is below 0°C (32°F),
drive the vehicle until ATF reaches its operating
temperature.
5) Disconnect the connector from transmis-
sion.
6) Measure the resistance between transmis-
sion connector terminals.
Connector & terminal
(T4) No. 11 — No. 15:Is the resistance 500 — 600
Ω?Go to step 6.Go to step 11.
6 CHECK ATF TEMPERATURE SENSOR.
Measure the resistance between transmission
connector terminals.
Connector & terminal
(T4) No. 11 — No. 15:Does the resistance value
increase when ATF tempera-
ture decreases?Go to step 7.Go to step 11.
7 PREPARE SUBARU SELECT MONITOR.Do you have a Subaru Select
Monitor?Go to step 9.Go to step 8.
8 CHECK INPUT SIGNAL FOR TCM.
1) Connect the connector to transmission.
2) Warm-up the transmission until ATF tem-
perature is about 80°C (176°F).
N
OTE:
If ambient temperature is below 0°C (32°F),
drive the vehicle until ATF reaches its operating
temperature.
3) Measure the voltage between TCM con-
nector terminal.
Connector & terminal
(B55) No. 9 (+) — No. 21 (
−):Is the voltage 1.5 — 1.9 V? Even if the POWER
indicator light was
blinking the circuit
has returned to a
normal condition at
this time. Tempo-
rary poor contact of
the connector or
harness may be the
cause. Repair the
harness or contact
in ATF temperature
sensor and trans-
mission connector.Go to step 10. Step Check Yes No

4AT(H4DOTC)-44
AUTOMATIC TRANSMISSION (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
9 CHECK INPUT SIGNAL FOR TCM USING
SUBARU SELECT MONITOR.
1) Connect the connector to transmission.
2) Turn the ignition switch to ON (engine
OFF).
3) Read the data of ATF temperature using the
Subaru Select Monitor. 15, OPERATION, Subaru Select Monitor.>Does the ATF temperature
gradually decrease?Even if the POWER
indicator light was
blinking, the circuit
has returned to a
normal condition at
this time. Tempo-
rary poor contact of
the connector or
harness may be the
cause. Repair the
harness or contact
in ATF temperature
sensor and trans-
mission connector.Go to step 10.
10 CHECK POOR CONTACT.Is there poor contact in ATF
temperature sensor circuit?Repair the poor
contact.Replace the TCM.
Transmission Con-
trol Module
(TCM).>
11 CHECK HARNESS CONNECTOR BETWEEN
TRANSMISSION AND ATF TEMPERATURE
SENSOR.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from transmis-
sion.
3) Remove the transmission connector from
bracket.
4) Lift-up the vehicle and place rigid racks.
NOTE:
Raise all wheels off floor.
5) Drain the ATF.
CAUTION:
Do not drain the ATF until it cools down.
6) Remove the oil pan, and disconnect the
connector from ATF temperature sensor con-
nector.
7) Measure the resistance of harness
between ATF temperature sensor and trans-
mission connector.
Connector & terminal
(T4) No. 11 — (AT11) No. 1:Is the resistance less than 1
Ω?Go to step 12.Repair the open
circuit in harness
between ATF tem-
perature sensor
and transmission
connector.
12 CHECK HARNESS CONNECTOR BETWEEN
TRANSMISSION AND ATF TEMPERATURE
SENSOR.
Measure the resistance of harness between
ATF temperature sensor and transmission con-
nector.
Connector & terminal
(T4) No. 15 — (AT11) No. 3:Is the resistance less than 1
Ω?Go to step 13.Repair the open
circuit in harness
between ATF tem-
perature sensor
and transmission
connector.
13 CHECK HARNESS CONNECTOR BETWEEN
TRANSMISSION AND ATF TEMPERATURE
SENSOR.
Measure the resistance of harness between
transmission connector and transmission
ground.
Connector & terminal
(T4) No. 11 — Transmission ground:Is the resistance more than 1
MΩ?Go to step 14.Repair the short
circuit in harness
between ATF tem-
perature sensor
and transmission
connector. Step Check Yes No