2004 SUBARU FORESTER replace disc

4AT(H4SO)-42
AUTOMATIC TRANSMISSION (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
Step Check Yes No
1 CHECK ENGINE GROUND TERMINALS.Have engine ground terminals
been tightened?Go to step 2.Tighten the engine
ground terminals.
2 CHECK GROUND CIRCUIT OF ECM.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from ECM.
3) Measure the resistance of harness
between ECM and engine ground.
Connector & terminal
(B134) No. 7 — Engine ground:
(B134) No. 35 — Engine ground:
(B135) No. 21 — Engine ground:
(B136) No. 26 — Engine ground:
(B136) No. 5 — Engine ground:
(B136) No. 16 — Engine ground:
(B137) No. 14 — Engine ground:Is the resistance less than 5
Ω?Go to step 3.Repair the open
circuit in harness
between ECM
connector and
engine grounding
terminal.
3 CHECK THROTTLE POSITION SENSOR.
1) Disconnect the connector from throttle
position sensor.
2) Measure the resistance between throttle
position sensor connector receptacle’s terminals.
Te r m i n a l s
No. 4 — No. 2:Is the resistance 3.0 — 4.2
kΩ?Go to step 4.Replace the throt-
tle position sensor.
4 CHECK THROTTLE POSITION SENSOR.
Measure the resistance between throttle posi-
tion sensor connector receptacle’s terminals.
Te r m i n a l s
No. 2 — No. 3:Is the resistance 0.35 — 0.5
kΩ?Go to step 5.Replace the throt-
tle position sensor.
5 CHECK HARNESS CONNECTOR BETWEEN
TCM AND THROTTLE POSITION SENSOR.
1) Disconnect the connector from TCM.
2) Measure the resistance of harness
between TCM and throttle position sensor con-
nector.
Connector & terminal
(B54) No. 3 — (E13) No. 3:Is the resistance less than 1
Ω?Go to step 6.Repair the open
circuit in harness
between TCM and
throttle position
sensor connector,
and poor contact
in coupling con-
nector.
6 CHECK HARNESS CONNECTOR BETWEEN
TCM AND THROTTLE POSITION SENSOR.
Measure the resistance of harness between
TCM and throttle position sensor connector.
Connector & terminal
(B54) No. 2 — (E13) No. 4:Is the resistance less than 1
Ω?Go to step 7.Repair the open
circuit in harness
between TCM and
throttle position
sensor connector,
and poor contact
in coupling con-
nector.
7 CHECK HARNESS CONNECTOR BETWEEN
TCM AND THROTTLE POSITION SENSOR.
Measure the resistance of harness between
TCM connector and chassis ground.
Connector & terminal
(B54) No. 3 — Chassis ground:Is the resistance more than 1
MΩ?Go to step 8.Repair the short
circuit in harness
between TCM and
throttle position
sensor connector.
8 CHECK HARNESS CONNECTOR BETWEEN
TCM AND THROTTLE POSITION SENSOR.
Measure the resistance of harness between
TCM connector and chassis ground.
Connector & terminal
(B54) No. 2 — Chassis ground:Is the resistance more than 1
MΩ?Go to step 9.Repair the short
circuit in harness
between TCM and
throttle position
sensor connector.

4AT(H4SO)-47
AUTOMATIC TRANSMISSION (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
Step Check Yes No
1 CHECK HARNESS CONNECTOR BETWEEN
TCM AND TRANSMISSION.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from TCM and
transmission.
3) Measure the resistance of harness
between TCM and transmission connector.
Connector & terminal
(B55) No. 18 — (B11) No. 17:Is the resistance less than 1
Ω?Go to step 2.Repair the open
circuit in harness
between TCM and
transmission con-
nector.
2 CHECK HARNESS CONNECTOR BETWEEN
TCM AND TRANSMISSION.
Measure the resistance of harness between
TCM and transmission connector.
Connector & terminal
(B54) No. 10 — (B11) No. 18:Is the resistance less than 1
Ω?Go to step 3.Repair the open
circuit in harness
between TCM and
transmission con-
nector, and poor
contact in cou-
pling connector.
3 CHECK HARNESS CONNECTOR BETWEEN
TCM AND TRANSMISSION.
Measure the resistance of harness between
TCM and chassis ground.
Connector & terminal
(B54) No. 10 — 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 TRANSMISSION.
Measure the resistance of harness between
TCM and chassis ground.
Connector & terminal
(B55) No. 18 — 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, and poor
contact in cou-
pling connector.
5 CHECK FRONT VEHICLE SPEED SENSOR.
Measure the resistance between transmission
connector receptacle’s terminals.
Connector & terminal
(T4) No. 17 — No. 18:Is the resistance 450 — 650
Ω?Go to step 6.Replace the front
vehicle speed sen-
sor. 55, Front Vehicle
Speed Sensor.>
6 PREPARE OSCILLOSCOPE.Do you have an oscilloscope? Go to step 9.Go to step 7.
7 PREPARE SUBARU SELECT MONITOR.Do you have a Subaru Select
Monitor?Go to step 10.Go to step 8.
8 CHECK INPUT SIGNAL FOR TCM.
1) Connect all connectors.
2) Lift-up or raise the vehicle and place rigid
rack.
NOTE:
Raise all wheels off floor.
3) Start the engine and set vehicle in 20 km/h
(12 MPH) condition.
NOTE:
The speed difference between front and rear
wheels may light the ABS warning light, but this
indicates no malfunction. When AT control diag-
nosis is finished, perform the ABS memory
clearance procedure of on-board diagnostics
system. Mode.>
4) Measure the voltage between TCM con-
nector terminals.
Connector & terminal
(B55) No. 18 (+) — (B54) No. 10 (
−):Is the voltage more than AC 1
V?Even if the
POWER indicator
light was blinking,
the circuit has
returned to a nor-
mal condition at
this time. A tempo-
rary poor contact
or harness may be
the cause. Repair
the harness or
connector in the
front vehicle speed
sensor circuit.Go to step 11.

4AT(H4SO)-50
AUTOMATIC TRANSMISSION (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
Step Check Yes No
1 CHECK TORQUE CONVERTER TURBINE
SPEED SENSOR.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from transmis-
sion.
3) Measure the resistance between transmis-
sion connector receptacle’s terminals.
Connector & terminal
(T4) No. 14 — No. 15:Is the resistance 450 — 650
Ω?Go to step 2.Replace the tur-
bine speed sensor.
Torque Converter
Turbine Speed
Sensor.>
2 CHECK HARNESS CONNECTOR BETWEEN
TCM AND TRANSMISSION.
1) Disconnect the connector from TCM.
2) Measure the resistance of harness
between TCM and transmission connector.
Connector & terminal
(B55) No. 8 — (B11) No. 14: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 TRANSMISSION.
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 4.Repair the open
circuit in harness
between TCM and
transmission con-
nector, and poor
contact in cou-
pling connector.
4 CHECK HARNESS CONNECTOR BETWEEN
TCM AND TRANSMISSION.
Measure the resistance of harness between
TCM 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 HARNESS CONNECTOR BETWEEN
TCM AND TRANSMISSION.
Measure the resistance of harness between
TCM and chassis ground.
Connector & terminal
(B55) No. 8 — Chassis ground:Is the resistance more than 1
MΩ?Go to step 6.Repair the short
circuit in harness
between TCM and
transmission con-
nector, and poor
contact in cou-
pling connector.
6 PREPARE OSCILLOSCOPE.Do you have an oscilloscope? Go to step 10.Go to step 7.
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 connectors to TCM and trans-
mission.
2) Start the engine and move select lever to
“P” or “N” range.
3) Measure the voltage between TCM con-
nector terminals.
Connector & terminal
(B55) No. 8 (+) — No. 9 (
−):Is the voltage more than AC 1
V?Even if the
POWER indicator
lights up, the cir-
cuit has returned
to a normal condi-
tion at this time. A
temporary poor
contact of the con-
nector or harness
may be the cause.
Repair the har-
ness or connector
in TCM and trans-
mission.Go to step 11.

4AT(H4SO)-57
AUTOMATIC TRANSMISSION (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
2 CHECK HARNESS CONNECTOR BETWEEN
TCM AND TRANSMISSION.
Measure the resistance of harness between
TCM connector and chassis ground.
Connector & terminal
(B54) No. 22 — Chassis ground:Is the resistance more than 1
MΩ?Go to step 3.Repair the short
circuit in harness
between TCM and
transmission con-
nector.
3 CHECK SHIFT SOLENOID 1.
Measure the resistance between transmission
connector terminals.
Connector & terminal
(T4) No. 1 — No. 16:Is the resistance 10 — 16 Ω? Go to step 4.Go to step 7.
4 CHECK OUTPUT SIGNAL EMITTED FROM
TCM.
1) Connect the connectors to TCM and trans-
mission.
2) Turn the ignition switch to ON (engine
OFF).
3) Move the select lever to “D” range.
4) Measure the voltage between TCM con-
nector and chassis ground.
Connector & terminal
(B54) No. 22 (+) — Chassis ground (
−):Is the voltage more than 9 V? Go to step 5.Go to step 6.
5 CHECK OUTPUT SIGNAL EMITTED FROM
TCM.
1) Turn the HOLD mode switch to ON.
2) Measure the voltage between TCM con-
nector and chassis ground.
Connector & terminal
(B54) No. 22 (+) — Chassis ground (
−):Is the voltage less than 1 V? Even if the
POWER indicator
light was blinking,
the circuit has
returned to a nor-
mal condition at
this time. A tempo-
rary poor contact
of the connector or
harness may be
the cause. Repair
the harness or
contact in TCM.Go to step 6.
6 CHECK POOR CONTACT.Is there poor contact in shift
solenoid 1 circuit?Repair poor con-
tact.Replace the TCM.
Transmission Con-
trol Module
(TCM).>
7 CHECK SHIFT SOLENOID 1 (IN TRANSMIS-
SION).
1) Remove the transmission connector from
bracket.
2) Lift-up or raise the vehicle and support with
rigid rack.
NOTE:
Raise all wheels off ground.
3) Drain the ATF.
CAUTION:
Do not drain the ATF until it cools down.
4) Remove the oil pan, and disconnect con-
nector from shift solenoid 1.
5) Measure the resistance between shift sole-
noid 1 connector and transmission ground.
Te r m i n a l s
No. 1 — Transmission ground:Is the resistance 10 — 16 Ω? Go to step 8.Replace the shift
solenoid 1. to 4AT-71, Shift
Solenoids, Duty
Solenoids and ATF
Temperature Sen-
sor.> Step Check Yes No

4AT(H4SO)-60
AUTOMATIC TRANSMISSION (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
Step Check Yes No
1 CHECK HARNESS CONNECTOR BETWEEN
TCM AND TRANSMISSION.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from TCM and
transmission.
3) Measure the resistance of harness
between TCM and shift solenoid 2 connector.
Connector & terminal
(B54) No. 5 — (B11) No. 2:Is the resistance less than 1
Ω?Go to step 2.Repair the open
circuit in harness
between TCM and
transmission con-
nector.
2 CHECK HARNESS CONNECTOR BETWEEN
TCM AND TRANSMISSION.
Measure the resistance of harness between
TCM connector and transmission ground.
Connector & terminal
(B54) No. 5 — Chassis ground:Is the resistance more than 1
MΩ?Go to step 3.Repair the short
circuit in harness
between TCM and
transmission con-
nector.
3 CHECK SHIFT SOLENOID 2.
Measure the resistance between transmission
connector terminals.
Connector & terminal
(T4) No. 2 — No. 16:Is the resistance 10 — 16 Ω? Go to step 4.Go to step 6.
4 CHECK OUTPUT SIGNAL EMITTED FROM
TCM.
1) Connect the connectors to TCM and trans-
mission.
2) Lift-up or raise the vehicle and support with
rigid rack.
N
OTE:
Raise all wheels off ground.
3) Start the engine and warm-up the transmis-
sion until ATF temperature is above 80°C
(176°F).
NOTE:
If ambient temperature is below 0°C (32°F),
drive the vehicle until ATF reaches its operating
temperature.
4) Move the selector lever to “D” range, and
slowly increase vehicle speed to 50 km/h (31
MPH).
NOTE:
The speed difference between front and rear
wheels may light the ABS warning light, but this
indicates no malfunction. When AT control diag-
nosis is finished, perform the ABS memory
clearance procedure of on-board diagnostics
system. Mode.>
5) Measure the voltage between TCM con-
nector and chassis ground.
Connector & terminal
(B54) No. 5 (+) — Chassis ground (
−):Is the voltage less than 1 V? Even if the
POWER indicator
light was blinking,
the circuit has
returned to a nor-
mal condition at
this time. A tempo-
rary poor contact
of the connector or
harness may be
the cause. Repair
the harness or
connector in TCM
and transmission.Go to step 5.
5 CHECK POOR CONTACT.Is there poor contact in shift
solenoid 2 circuit?Repair the poor
contact.Replace the TCM.
Transmission Con-
trol Module
(TCM).>

4AT(H4SO)-61
AUTOMATIC TRANSMISSION (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
6 CHECK SHIFT SOLENOID 2 (IN TRANSMIS-
SION).
1) Remove the transmission connector from
bracket.
2) Drain the ATF.
CAUTION:
Do not drain the ATF until it cools down.
3) Remove the oil pan, and disconnect con-
nector from shift solenoid 2.
4) Measure the resistance between shift sole-
noid 2 connector and transmission ground.
Connector & terminal
No. 1 — Transmission ground:Is the resistance 10 — 16 Ω? Go to step 7.Replace the shift
solenoid 2 assem-
bly. 71, Shift Sole-
noids, Duty Sole-
noids and ATF
Temperature Sen-
sor.>
7 CHECK HARNESS CONNECTOR BETWEEN
SHIFT SOLENOID 2 AND TRANSMISSION.
Measure the resistance of harness between
shift solenoid 2 and transmission connector.
Connector & terminal
(AT6) No. 1 — (T4) No. 2:Is the resistance less than 1
Ω?Go to step 8.Repair the open
circuit in harness
between shift sole-
noid 2 and trans-
mission connector.
8 CHECK HARNESS CONNECTOR BETWEEN
SHIFT SOLENOID 2 AND TRANSMISSION.
Measure the resistance of harness between
shift solenoid 2 connector and transmission
ground.
Connector & terminal
(T4) No. 2 — Transmission ground:Is the resistance more than 1
MΩ?Even if the
POWER indicator
light was blinking,
the circuit has
returned to a nor-
mal condition at
this time. A tempo-
rary poor contact
of the connector or
harness may be
the cause. Repair
the harness or
connector in shift
solenoid 2 and
transmission.Repair the short
circuit harness
between shift sole-
noid 2 and trans-
mission connector. Step Check Yes No

4AT(H4SO)-63
AUTOMATIC TRANSMISSION (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
Step Check Yes No
1 CHECK HARNESS CONNECTOR BETWEEN
TCM AND TRANSMISSION.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from TCM and
transmission.
3) Measure the resistance of harness
between TCM and transmission connector.
Connector & terminal
(B54) No. 15 — (B11) No. 3:Is the resistance less than 1
Ω?Go to step 2.Repair the open
circuit in harness
between TCM and
transmission con-
nector.
2 CHECK HARNESS CONNECTOR BETWEEN
TCM AND TRANSMISSION.
Measure the resistance of harness between
TCM connector and chassis ground.
Connector & terminal
(B54) No. 15 — Chassis ground:Is the resistance more than 1
MΩ?Go to step 3.Repair the short
circuit in harness
between TCM and
transmission con-
nector.
3 CHECK LOW CLUTCH TIMING SOLENOID.
Measure the resistance between transmission
connector terminals.
Connector & terminal
(T4) No. 3 — No. 16:Is the resistance 10 — 16 Ω? Go to step 4.Go to step 7.
4 CHECK OUTPUT SIGNAL EMITTED FROM
TCM.
1) Connect the connectors to TCM and trans-
mission.
2) Turn the ignition switch to ON (engine
OFF).
3) Move the select lever to “D” range.
4) Measure the voltage between TCM con-
nector and chassis ground.
Connector & terminal
(B54) No. 15 (+) — Chassis ground (
−):Is the voltage more than 9 V? Go to step 5.Go to step 6.
5 CHECK OUTPUT SIGNAL EMITTED FROM
TCM.
1) Turn the HOLD mode switch to ON.
2) Measure the voltage between TCM con-
nector and chassis ground.
Connector & terminal
(B54) No. 15 (+) — Chassis ground (
−):Is the voltage less than 1 V? Even if the
POWER indicator
light was blinking,
the circuit has
returned to a nor-
mal condition at
this time. A tempo-
rary poor contact
of the connector or
harness may be
the cause. Repair
the harness or
contact in TCM
and transmission.Go to step 6.
6 CHECK POOR CONTACT.Is there poor contact in low
clutch timing solenoid circuit?Repair the poor
contact.Replace the TCM.
Transmission Con-
trol Module
(TCM).>

4AT(H4SO)-64
AUTOMATIC TRANSMISSION (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
7 CHECK LOW CLUTCH TIMING SOLENOID
(IN TRANSMISSION).
1) Remove the transmission connector from
bracket.
2) Lift-up or raise the vehicle and support with
rigid rack.
N
OTE:
Raise all wheels off ground.
3) Drain the ATF.
CAUTION:
Do not drain the ATF until it cools down.
4) Remove the oil pan, and disconnect con-
nector from low clutch timing solenoid.
5) Measure the resistance between low clutch
timing solenoid connector and transmission
ground.
Te r m i n a l s
No. 1 — Transmission ground:Is the resistance 10 — 16 Ω? Go to step 8.Replace the low
clutch timing sole-
noid. 71, Shift Sole-
noids, Duty Sole-
noids and ATF
Temperature Sen-
sor.>
8 CHECK HARNESS CONNECTOR BETWEEN
LOW CLUTCH TIMING SOLENOID AND
TRANSMISSION.
Measure the resistance of harness between
low clutch timing solenoid and transmission
connector.
Connector & terminal
(AT9) No. 1 — (AT4) No. 3:Is the resistance less than 1
Ω?Go to step 9.Repair the open
circuit in harness
between low clutch
timing solenoid
and transmission
connector.
9 CHECK HARNESS CONNECTOR BETWEEN
LOW CLUTCH TIMING SOLENOID AND
TRANSMISSION.
Measure the resistance of harness between
low clutch timing solenoid connector and trans-
mission ground.
Connector & terminal
(T4) No. 3 — Transmission ground:Is the resistance more than 1
MΩ?Even if the
POWER indicator
light was blinking,
the circuit has
returned to a nor-
mal condition at
this time. A tempo-
rary poor contact
of the connector or
harness may be
the cause. Repair
the harness or
connector in low
clutch timing sole-
noid and transmis-
sion.Repair the short
circuit harness
between low clutch
timing solenoid
and transmission
connector. Step Check Yes No