2004 SUBARU FORESTER engine oil

4AT(H4SO)-111
AUTOMATIC TRANSMISSION (DIAGNOSTIC)
Symptom Related Diagnostic
Vehicle does not start in any shift range (engine revving up). Strainer
 Line pressure duty solenoid
 Control valve
 Drive pinion
 Hypoid gear
Axle shaft
 Differential gear
 Oil pump
 Input shaft
 Output shaft
 Planetary gear
Drive plate
 ATF level too low
 Front gasket transmission case
Vehicle does not start in “R” range only (engine revving up). Select cable
 Select lever
 Control valve
 Low & reverse clutch
 Reverse clutch
Vehicle does not start in “R” range only (engine stalls). Low clutch
2-4 brake
 Planetary gear
 Parking brake mechanism
Vehicle does not start in “D”, “3” range only (engine revving up). Low clutch
 One-way clutch
Vehicle does not start in “D”, “3” or “2” range only (engine rev-
ving up). Low clutch
Vehicle does not start in “D”, “3” or “2” range only (engine stalls).  Reverse clutch
Vehicle starts in “R” range only (engine revving up).  Control valve
Acceleration during standing starts is poor (high stall rpm). Control valve
 Low clutch
 Reverse clutch
 ATF level too low
 Front gasket transmission case
 Differential gear oil level too high or too low
Acceleration during standing starts is poor (low stall rpm). Oil pump
 Torque converter one-way clutch
 Engine performance
Acceleration is poor when select lever is in “D”, “3” or “2” range
(normal stall rpm).TCM
 Control valve
High clutch
2-4 brake
 Planetary gear
Acceleration is poor when select lever is in “R” (normal stall rpm). Control valve
High clutch
2-4 brake
 Planetary gear
No shift occurs from 1st to 2nd gear.TCM
 Rear vehicle speed sensor
 Front vehicle speed sensor
 Throttle position sensor
 Shift solenoid 1
 Control valve
2-4 brake
No shift occurs from 2nd to 3rd gear.TCM
 Control valve
High clutch
 Shift solenoid 2 Symptom Problem parts

4AT(H4SO)-112
AUTOMATIC TRANSMISSION (DIAGNOSTIC)
Symptom Related Diagnostic
No shift occurs from 3rd to 4th gear.TCM
 Shift solenoid 1
 ATF temperature sensor
 Control valve
2-4 brake
Engine brake is not effected when select lever is in “3” range. Inhibitor switch
TCM
 Throttle position sensor
 Control valve
Engine brake is not effected when select lever is in “3” or “2”
range. Control valve
Engine brake is not effected when select lever is in “1” range. Control valve
 Low & reverse brake
Shift characteristics are erroneous. Inhibitor switch
TCM
 Front vehicle speed sensor
 Rear vehicle speed sensor
 Throttle position sensor
 Control valve
 Ground earth
No lock-up occurs.TCM
 Throttle position sensor
 ATF temperature sensor
 Control valve
 Lock-up facing
 Engine speed signal
Parking brake is not effected.  Select cable
 Select lever
 Parking mechanism Shift lever cannot be moved or is hard to move from “P” range.
ATF spurts out.  ATF level too high
Differential oil spurts out.  Differential gear oil too high
Differential oil level changes excessively. Seal pipe
 Double oil seal
Odor is produced from ATF supply pipe.High clutch
2-4 brake
 Low & reverse clutch
 Reverse clutch
 Lock-up facing
 ATF deterioration
Shock occurs from 1st to 2nd gear.TCM
 Throttle position sensor
 2-4 brake duty solenoid
 ATF temperature sensor
 Line pressure duty solenoid
 Control valve
2-4 brake
 ATF deterioration
 Engine performance
 2-4 brake timing solenoid
Slippage occurs from 1st to 2nd gear.TCM
 Throttle position sensor
 2-4 brake duty solenoid
 ATF temperature sensor
 Line pressure duty solenoid
 Control valve
2-4 brake
 2-4 brake timing solenoid
High clutch Symptom Problem parts

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

4AT(H4DOTC)-71
AUTOMATIC TRANSMISSION (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
8 CHECK OUTPUT SIGNAL FROM TCM US-
ING SUBARU SELECT MONITOR.
1) Fully open the throttle.
2) Shift the select lever to “R” range. (engine
OFF)
3) Read the data of line pressure linear sole-
noid.Is the value 20 — 40%? Even if the POWER
indicator light was
blinking, the circuit
has returned to a
normal condition at
this time. A tempo-
rary poor contact of
the connector or
harness may be the
cause. Repair the
harness or connec-
tor in transmission.Go to step 9.
9 CHECK POOR CONTACT.Is there poor contact in line
pressure linear solenoid cir-
cuit?Repair the poor
contact.Replace the TCM.
Transmission Con-
trol Module
(TCM).>
10 CHECK LINE PRESSURE LINEAR SOLE-
NOID (IN TRANSMISSION).
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 line pressure linear solenoid.
4) Measure the resistance between line pres-
sure linear solenoid connector and transmis-
sion ground.
Connector & terminal
(AT11) No. 2 — No. 4:Is the resistance 2.0 — 4.5 Ω? Go to step 11.Replace the con-
trol valve body.
Control Valve
Body.>
11 CHECK HARNESS CONNECTOR BETWEEN
TRANSMISSION AND LINE PRESSURE LIN-
EAR SOLENOID.
Measure the resistance of harness between
line pressure linear solenoid and transmission
connector.
Connector & terminal
(T4) No. 2 — (AT11) No. 4:
(T4) No. 1 — (AT11) No. 2:Is the resistance less than 1
Ω?Go to step 12.Repair the open cir-
cuit in harness
between line pres-
sure linear solenoid
and transmission
connector.
12 CHECK HARNESS CONNECTOR BETWEEN
TRANSMISSION AND LINE PRESSURE LIN-
EAR SOLENOID.
Measure the resistance of harness between
transmission connector and transmission
ground.
Connector & terminal
(T4) No. 1 — Transmission ground:
(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
normal condition at
this time. A tempo-
rary poor contact of
the connector or
harness may be the
cause. Repair the
harness or connec-
tor in line pressure
linear solenoid and
transmission.Repair the short
circuit in harness
between line pres-
sure linear sole-
noid and
transmission con-
nector. Step Check Yes No

4AT(H4DOTC)-74
AUTOMATIC TRANSMISSION (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
7 CHECK OUTPUT SIGNAL FROM TCM US-
ING SUBARU SELECT MONITOR.
1) Connect the connectors to TCM and trans-
mission.
2) Connect the Subaru Select Monitor to data
link connector.
3) Start the engine and turn Subaru Select
Monitor switch to ON.
4) Warm-up the transmission until ATF tem-
perature is above 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) Stop the engine and turn ignition switch to
ON (engine OFF).
6) Shift the select lever to “P” or “N” range.
7) Read the data of low clutch duty solenoid
using Subaru Select Monitor.
 Low clutch duty solenoid is indicated in “%”.Is the value 100%? Go to step 8.Go to step 9.
8 CHECK OUTPUT SIGNAL FROM TCM US-
ING SUBARU SELECT MONITOR.
1) Turn the ignition switch to ON (engine
OFF).
2) Shift the select lever to “D” range.
3) Read the data of low clutch duty solenoid.Is the value 0%? Even if the POWER
indicator light was
blinking, the circuit
has returned to a
normal condition at
this time. A tempo-
rary poor contact of
the connector or
harness may be the
cause. Repair the
harness or connec-
tor in transmission.Go to step 9.
9 CHECK POOR CONTACT.Is there poor contact in low
clutch duty solenoid circuit?Repair the poor
contactReplace the TCM.
Transmission Con-
trol Module
(TCM).>
10 CHECK LOW CLUTCH DUTY SOLENOID (IN
TRANSMISSION).
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 low clutch duty solenoid.
4) Measure the resistance between low clutch
duty solenoid connector and transmission
ground.
Connector & terminal
(AT12) No. 2 — Transmission ground:Is the resistance 2.0 — 4.5 Ω? Go to step 11.Replace the con-
trol valve body.
Control Valve
Body.>
11 CHECK HARNESS CONNECTOR BETWEEN
TRANSMISSION AND LOW CLUTCH DUTY
SOLENOID.
Measure the resistance of harness between
low clutch duty solenoid and transmission con-
nector.
Connector & terminal
(T4) No. 4 — (AT12) No. 2:Is the resistance less than 1
Ω?Go to step 12.Repair the open
circuit in harness
between low clutch
duty solenoid and
transmission con-
nector. Step Check Yes No

4AT(H4DOTC)-126
AUTOMATIC TRANSMISSION (DIAGNOSTIC)
Symptom Related Diagnostic
15.Symptom Related Diagnostic
A: INSPECTION
Symptom Problem parts
Starter does not rotate when select lever is in “P” or “N” range,
starter rotates when select lever is in “R”, “D”, “3” or “2” range. Inhibitor switch
 Select cable
 Select lever
 Starter motor and harness
Abnormal noise when select lever is in “P” or “N” range. Strainer
 Transfer duty solenoid
 Oil pump
Drive plate
 ATF level too high or too low
Hissing noise occurs during standing start. Strainer
 ATF level too high or too low
Noise occurs while driving in “D1”.  Final gear
 Planetary gear
 Reduction gear
 Differential gear oil level too high or too low Noise occurs while driving in “D2”.
Noise occurs while driving in “D3”. Final gear
 Low & reverse brake
 Reduction gear
 Differential gear oil level too high or too low
Noise occurs while driving in “D4”. Final gear
 Low & reverse brake
 Planetary gear
 Reduction gear
 Differential gear oil level too high or too low
Engine stalls while shifting from “1” range to another. Control valve
 Lock-up damper
 Engine performance
 Input shaft
Vehicle moves when select lever is in “N” range. Select cable
 Inhibitor switch
TCM
 Low clutch
Shock occurs when select lever is shifted from “N” to “D” range. Accelerator pedal position sensor
 ATF temperature sensor
 Line pressure linear solenoid
 Low clutch duty solenoid
 Low clutch
TCM
Harness
 Control valve
 ATF deterioration
Excessive time lag occurs when select lever is shifted from “N”
to “D” range. Control valve
 Low clutch
 Line pressure duty solenoid
 Seal ring
 Front gasket of transmission case
Shock occurs when select lever is shifted from “N” to “R” range. Accelerator pedal position sensor
 ATF temperature sensor
 Line pressure linear solenoid
TCM
Harness
 Control valve
 ATF deterioration

4AT(H4DOTC)-127
AUTOMATIC TRANSMISSION (DIAGNOSTIC)
Symptom Related Diagnostic
Excessive time lag occurs when select lever is shifted from “N”
to “R” range. Control valve
 Low & reverse clutch
 Reverse clutch
 Line pressure linear solenoid
 Seal ring
 Front gasket of transmission case
Vehicle does not start in any shift range (engine stalls). Parking brake mechanism
 Planetary gear
Vehicle does not start in any shift range (engine revving up). Strainer
 Line pressure linear solenoid
 Control valve
 Drive pinion
 Hypoid gear
Axle shaft
 Differential gear
 Oil pump
 Input shaft
 Output shaft
 Planetary gear
Drive plate
 ATF level too low
 Front gasket of transmission case
Vehicle does not start in “R” range only (engine revving up). Select cable
 Select lever
 Line pressure linear solenoid
 Control valve
 Low & reverse clutch
 Reverse clutch
Vehicle does not start in “R” range only (engine stalls). Low clutch
2-4 brake
 Planetary gear
 Parking brake mechanism
Vehicle does not start in “D”, “3” range only (engine revving up). Low clutch
 One-way clutch
Vehicle does not start in “D”, “3” or “2” range only (engine rev-
ving up).Low clutch
Vehicle does not start in “D”, “3” or “2” range only (engine
stalls).Reverse clutch
Vehicle starts in “R” range only (engine revving up).  Control valve
Acceleration during standing starts is poor (high stall rpm). Control valve
 Low clutch
 Reverse clutch
 ATF level too low
 ATF deterioration
 Front gasket of transmission case
 Differential gear oil level too high or too low
Acceleration during standing starts is poor (low stall rpm). Oil pump
 Torque converter one-way clutch
 Engine performance
Acceleration is poor when select lever is in “D”, “3” or “2” range
(normal stall rpm).TCM
 Control valve
High clutch
2-4 brake
 Planetary gear
Acceleration is poor when select lever is in “R” (normal stall
rpm). Control valve
High clutch
2-4 brake
 Planetary gear Symptom Problem parts

4AT(H4DOTC)-128
AUTOMATIC TRANSMISSION (DIAGNOSTIC)
Symptom Related Diagnostic
No shift occurs from 1st to 2nd gear.TCM
 Rear vehicle speed sensor
 Front vehicle speed sensor
 Throttle position sensor
 Control valve
2-4 brake
No shift occurs from 2nd to 3rd gear.TCM
 Control valve
High clutch
No shift occurs from 3rd to 4th gear.TCM
 ATF temperature sensor
 Control valve
2-4 brake
Engine brake is not effected when select lever is in “3” range. Inhibitor switch
TCM
 Throttle position sensor
 Control valve
Engine brake is not effected when select lever is in “3” or “2”
range.Control valve
Engine brake is not effected when select lever is in “1” range. Control valve
 Low & reverse brake
Shift characteristics are erroneous. Inhibitor switch
TCM
 Front vehicle speed sensor
 Rear vehicle speed sensor
 Throttle position sensor
 Control valve
 Ground earth
No lock-up occurs.TCM
 Torque converter turbine speed sensor
 Throttle position sensor
 ATF temperature sensor
 Control valve
 Lock-up facing
 Engine speed signal
Parking brake is not effected.  Select cable
 Select lever
 Parking mechanism Shift lever cannot be moved or is hard to move from “P” range.
ATF spurts out. ATF level too high
Differential oil spurts out. Differential gear oil too high
Differential oil level changes excessively. Seal pipe
 Double oil seal
Odor is produced from ATF supply pipe.High clutch
2-4 brake
 Low & reverse clutch
 Reverse clutch
 Lock-up facing
 ATF deterioration
Shock occurs from 1st to 2nd gear.TCM
 Torque converter turbine speed sensor
 Accelerator pedal position sensor
 2-4 brake duty solenoid
 ATF temperature sensor
 Line pressure linear solenoid
 Control valve
2-4 brake
 ATF deterioration
 Engine performance
 Low & reverse duty solenoid Symptom Problem parts