2004 SUBARU FORESTER engine

4AT(H4SO)-16
AUTOMATIC TRANSMISSION (DIAGNOSTIC)
Transmission Control Module (TCM) I/O Signal
(1) Transmission control module
(TCM)(17) “P” range indicator light (35) Torque control signal 2
(18) “P” range switch (36) Torque control signal 1
(2) Cruise control module (19) “R” range indicator light (37) Intake manifold pressure signal
(3) ABS control module (20) “R” range switch (38) AT diagnostics signal
(4) Ignition switch (21) “N” range indicator light (39) Engine control module (ECM)
(5) Brake switch (22) “N” range switch (40) ATF temperature sensor
(6) Brake light (23) “D” range indicator light (41) Torque converter turbine speed
sensor
(7) Battery (24) “D” range switch
(8) Combination meter (Speedome-
ter circuit)(25) “3” range indicator light (42) Rear vehicle speed sensor
(26) “3” range switch (43) Front vehicle speed sensor
(9) AT OIL TEMP warning light (27) “2” range indicator light (44) Shift solenoid 1
(10) FWD indicator light (28) “2” range switch (45) Shift solenoid 2
(11) POWER indicator light (29) “1” range indicator light (46) 2-4 brake timing solenoid
(12) FWD switch (30) “1” range switch (47) Line pressure duty solenoid
(13) POWER switch (31) Data link connector (48) 2-4 brake duty solenoid
(14) Kick-down switch (32) Throttle position sensor (49) Lock-up duty solenoid
(15) Hold indicator light (33) Engine speed signal (50) Low clutch timing solenoid
(16) HOLD switch (34) Torque control cut signal (51) Transfer duty solenoid

4AT(H4SO)-17
AUTOMATIC TRANSMISSION (DIAGNOSTIC)
Subaru Select Monitor
6. Subaru Select Monitor
A: OPERATION
1. READ DIAGNOSTIC TROUBLE CODE
(DTC)
1) Prepare the Subaru Select Monitor kit.
2) Connect the diagnosis cable to Subaru Select
Monitor.
3) Insert the cartridge into Subaru Select Monitor.
General Description.>
4) Connect the Subaru Select Monitor to data link
connector.
(1) Data link connector located in the lower por-
tion of instrument panel (on driver’s side).
(2) Connect the diagnosis cable to data link con-
nector.
NOTE:
Do not connect scan tools except for Subaru Select
Monitor and OBD-II general scan tool.5) Turn the ignition switch to ON (engine OFF) and
Subaru Select Monitor switch to ON.
6) On the «Main Menu» display screen, select the
{Each System Check} and press the [YES] key.
7) On the «System Selection Menu» display screen,
select the {Transmission Control System} and press
the [YES] key.
8) Press the [YES] key after the information of
transmission type is displayed.
9) On the «Transmission Diagnosis» display screen,
select the {DTC Display} and press the [YES] key.
10) On the «DTC Display» display screen, select
the {Memorized DTC} and press the [YES] key.
NOTE:
 For detailed operation procedure, refer to the
SUBARU SELECT MONITOR OPERATION MAN-
UAL.
 For details concerning the DTC, refer to the List of
Diagnostic Trouble Code (DTC). 4AT(H4SO)-35, List of Diagnostic Trouble Code
(DTC).>
AT-00338
AT-00339
AT-00422
(A) POWER switch
(A)
AT-00341

4AT(H4SO)-18
AUTOMATIC TRANSMISSION (DIAGNOSTIC)
Subaru Select Monitor
2. READ CURRENT DATA
1) On the «Main Menu» display screen, select the {Each System Check} and press the [YES] key.
2) On the «System Selection Menu» display screen, select the {Transmission Control System} and press the
[YES] key.
3) Press the [YES] key after the information of transmission type is displayed.
4) On the «Transmission Diagnosis» display screen, select the {Current Data Display & Save} and press the
[YES] key.
5) On the «Data Display Menu» display screen, select the {Data Display} and press the [YES] key.
6) Using the scroll key, move the display screen up or down until desired data is shown.
 A list of the support data is shown in the following table.
NOTE:
For detailed operation procedure, refer to the SUBARU SELECT MONITOR OPERATION MANUAL.
Contents Display Unit of measure
Battery voltage Battery Voltage V
Rear vehicle speed sensor signal Rear Wheel Speed km/h or MPH
Front vehicle speed sensor signal Front Wheel Speed km/h or MPH
Engine speed signal Engine Speed rpm
Automatic transmission fluid temperature signal ATF Temp.°C or °F
Throttle position signal Throttle Sensor Voltage V
Gear position Gear Position —
Line pressure control duty ratio Line Pressure Duty Ratio %
Lock up clutch control duty ratio Lock Up Duty Ratio %
Transfer clutch control duty ratio (AWD model) Transfer Duty Ratio %
Power supply for throttle position sensor Throttle Sensor Power V
Torque converter turbine speed signal Turbine Revolution Speed rpm
2-4 brake timing pressure control duty ratio Brake Clutch Duty Ratio %
Intake manifold pressure sensor voltage Mani. Pressure Voltage V
FWD switch signal FWD Switch ON or OFF
Stop light switch signal Stop Light Switch ON or OFF
Anti lock brake system signal ABS Signal ON or OFF
Cruise control system signal Cruise Control Signal ON or OFF
Parking range signal P Range Signal ON or OFF
Neutral range signal N Range Signal ON or OFF
Reverse range signal R Range Signal ON or OFF
Drive range signal D Range Signal ON or OFF
3rd range signal 3rd Range Signal ON or OFF
2nd range signal 2nd Range Signal ON or OFF
1st range signal 1st Range Signal ON or OFF
Shift control solenoid A Shift Solenoid #1 ON or OFF
Shift control solenoid B Shift Solenoid #2 ON or OFF
Torque control output signal #1 Torque Control Signal 1 ON or OFF
Torque control output signal #2 Torque Control Signal 2 ON or OFF
Torque control cut signal Torque Control Cut Sig. ON or OFF
2-4 brake timing control solenoid valve 2-4 Brake Timing Sol. ON or OFF
Low clutch timing control solenoid valve Low Clutch Timing Sol. ON or OFF
Automatic transmission diagnosis indicator lamp Diagnosis Lamp ON or OFF
Power mode switch signal Power Mode Switch ON or OFF
Hold mode switch signal Hold Mode Switch ON or OFF
Kick down switch signal Kick Down Switch ON or OFF
Automatic transmission fluid temperature lamp ATF Temperature Lamp ON or OFF

4AT(H4SO)-20
AUTOMATIC TRANSMISSION (DIAGNOSTIC)
Read Diagnostic Trouble Code (DTC)
7. Read Diagnostic Trouble Code (DTC)
A: OPERATION
1. WITHOUT SUBARU SELECT MONITOR
Step Check Yes No
1 PERFORM READ DTC.
1) Warm-up the engine.
2) Turn the ignition switch to OFF.
3) Turn the ignition switch to ON.
4) Start the engine.
5) Drive the vehicle at speeds greater than 20
km/h (12 MPH).
6) Stop the vehicle.
7) The brake pedal depressed and move
select lever to 1 range.
8) Turn the ignition switch to OFF.
9) Turn the ignition switch to ON.
10)Move the select lever “2” range.
11)Move the select lever “1” range.
12)Move the select lever “2” range.
13)Move the select lever “3” range.
14)Move the select lever “D” range.Does the POWER indicator
light blink at 4 Hz intervals?
NOTE: Blinks every 0.125 (1/8)
seconds (until the ignition
switch is turned OFF).Go to step 2.Repair the power
supply and ground
circuit. 4AT(H4SO)-30,
CHECK POWER
SUPPLY AND
GROUND LINE,
INSPECTION,
Power Indicator
Light Display.>
2 CHECK POWER INDICATOR LIGHT.Does the POWER indicator
light blink at 2 Hz intervals?
NOTE: Blinks every 0.25 (1/4)
seconds (until ignition switch is
turned to OFF).The AT system is
normal.Go to step 3.
3 CHECK POWER INDICATOR LIGHT.Is the DTC outputted by the
blink of POWER indicator
light?Inspect the prob-
lem correspond-
ing with DTC.
N
OTE:
Record all DTCs.Go to step 4.
4 CHECK POWER INDICATOR LIGHT.Does the POWER indicator
light remain illuminated?Repair the
POWER indicator
light circuit to 4AT(H4SO)-25,
INSPECTION,
Power Indicator
Light Display.>, or
Inspect inhibitor
switch, wiring,
TCM, etc.Calling up the DTC
again.

4AT(H4SO)-24
AUTOMATIC TRANSMISSION (DIAGNOSTIC)
Power Indicator Light Display
10.Power Indicator Light Display
A: OPERATION
When any on-board diagnostics item is malfunctioning, the display on POWER indicator light blinks from the
time malfunction is detected after starting the engine until ignition switch is turned to OFF. The malfunctioning
part or unit can be determined by a DTC during on-board diagnostics operation. Problems which occurred
previously can also be identified through the memory function. If the Power indicator does not show a prob-
lem (although a problem is occurring), the problem can be determined by checking the performance charac-
teristics of each sensor using select monitor. The indicator signal is as shown in the figure.
Perform the inspection when the POWER indicator light does not operate correctly. INSPECTION, Power Indicator Light Display.>
(A) Ignition switch (engine OFF) (C) Faulty (engine ON) (D) Normal (POWER switch ON)
(B) Normal (engine ON)
(1) ON (4) 0.25 sec. (6) POWER switch ON
(2) OFF (5) Blink (7) POWER switch OFF
(3) 2 sec.
AT-01109
(4)
(3)
(1)
(2)
(1)
(2)
(1)
(2)
(1)
(2)(3)
(3)(5)
(6) (A)
(B)
(C)
(D)
(7)

4AT(H4SO)-25
AUTOMATIC TRANSMISSION (DIAGNOSTIC)
Power Indicator Light Display
B: INSPECTION
1. INSPECTION OF POWER INDICATOR LIGHT
DETECTING CONDITION:
The Power Indicator light circuit is open or shorted.
TROUBLE SYMPTOM:
 When the ignition switch is turned to ON (engine OFF), POWER indicator light does not illuminate.
 When the on-board diagnostics is performed, POWER indicator light remains illuminated.

4AT(H4SO)-28
AUTOMATIC TRANSMISSION (DIAGNOSTIC)
Power Indicator Light Display
Step Check Yes No
1 CHECK POWER INDICATOR LIGHT.
Turn the ignition switch to ON (engine OFF).Does the POWER indicator
light illuminate?Go to step 3.Go to step 2.
2 CHECK POWER INDICATOR LIGHT.
1) Turn the ignition switch to OFF.
2) Remove the combination meter.
3) Remove the POWER indicator light bulb
from combination meter.Is the POWER indicator light
bulb OK?Go to step 4.Replace the
POWER indicator
light bulb.
3 CHECK POWER INDICATOR LIGHT.
Perform “Read Diagnostic Trouble Code
(DTC)”. nostic Trouble Code (DTC).>Does the POWER indicator
light blink?A temporary poor
contact of the con-
nector or harness
may be the cause.
Repair the har-
ness or connector
in TCM, inhibitor
switch and combi-
nation meter.Go to step 9.
4 CHECK FUSE (No. 14).
Remove the fuse (No. 14).Is the fuse (No. 14) blown out? Replace the fuse
(No. 14). If
replaced fuse (No.
14) is blown out
easily, repair short
circuit in harness
between fuse (No.
14) and combina-
tion meter.Go to step 5.
5 CHECK HARNESS CONNECTOR BETWEEN
COMBINATION METER AND IGNITION
SWITCH.
1) Turn the ignition switch to ON (engine
OFF).
2) Measure the voltage between combination
meter connector and chassis ground.
Connector & terminal
(i10) No. 9 (+) — Chassis ground (
−):Is the voltage more than 9 V? Go to step 6.Repair the open
circuit in harness
between combina-
tion meter and bat-
tery.
6 CHECK COMBINATION METER.
Measure the voltage between combination
meter connector and chassis ground.
Connector & terminal
(i11) No. 2 (+) — Chassis ground (
−):Is the voltage less than 9 V? Repair the combi-
nation meter.
Combination
Meter Assembly.>Go to step 7.
7 CHECK OPEN CIRCUIT OF HARNESS.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from combination
meter connector.
3) Measure the resistance of harness
between combination meter.
Connector & terminal
(B56) No. 11 — (i11) No. 2:Is the resistance less than 1
Ω?Go to step 8.Repair the open
circuit in harness
between TCM and
combination
meter, and poor
contact in cou-
pling connector.
8 CHECK INPUT SIGNAL FOR TCM.
1) Connect the connector to TCM and combi-
nation meter.
2) Turn the ignition switch to ON (engine
OFF).
3) Measure the voltage between TCM con-
nector and chassis ground.
Connector & terminal
(B56) No. 11 (+) — Chassis ground (
−):Is the voltage less than 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.Replace the TCM.
Transmission Con-
trol Module
(TCM).>

4AT(H4SO)-31
AUTOMATIC TRANSMISSION (DIAGNOSTIC)
Power Indicator Light Display
Step Check Yes No
1 CHECK BATTERY TERMINAL.
Turn the ignition switch to OFF.Is there poor contact at battery
terminal?Repair or tighten
the battery termi-
nal.Go to step 2.
2 CHECK POWER SUPPLY OF TCM.
1) Disconnect the connector from TCM.
2) Turn the ignition switch to ON.
3) Measure the voltage between TCM con-
nector and chassis ground.
Connector & terminal
(B56) No. 1 (+) — Chassis ground (
−):Is the voltage 10 — 13 V? Go to step 4.Go to step 3.
3 CHECK FUSE (NO. 4).
Remove the fuse (No. 4).Is the fuse (No. 4) blown out? Replace the fuse
(No. 4). If replaced
fuse (No. 4) has
blown out easily,
repair short circuit
in harness
between fuse (No.
4) and TCM.Repair the open
circuit in harness
between fuse (No.
4) and TCM, or
fuse (No. 4) and
battery, and poor
contact in cou-
pling connector.
4 CHECK IGNITION POWER SUPPLY CIR-
CUIT.
1) Turn the ignition switch to ON (engine
OFF).
2) Measure the ignition power supply voltage
between TCM connector and chassis ground.
Connector & terminal
(B54) No. 23 (+) — Chassis ground (–):
(B54) No. 24 (+) — Chassis ground (–):Is the voltage 10 — 13 V? Go to step 6.Go to step 5.
5 CHECK FUSE (NO. 11).
Remove the fuse (No. 11).Is the fuse (No. 11) blown out? Replace the fuse
(No. 11). If
replaced fuse (No.
11) has blown out
easily, repair short
circuit in harness
between fuse (No.
11) and TCM.Repair the open
circuit in harness
between fuse (No.
11) and TCM, or
fuse (No. 11) and
battery, and poor
contact in cou-
pling connector.
6 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
(B56) No. 19 — (B11) No. 16:
(B54) No. 21 — (B11) No. 16:Is the resistance less than 1
Ω?Go to step 7.Repair the open
circuit in harness
between TCM,
transmission har-
ness connector,
and poor contact
in coupling con-
nector.
7 CHECK HARNESS CONNECTOR BETWEEN
TRANSMISSION AND TRANSMISSION
GROUND.
Measure the resistance of harness between
transmission and transmission ground.
Connector & terminal
(T4) No. 16 — Transmission ground:Is the resistance less than 1
Ω?Go to step 8.Repair the open
circuit in harness
between transmis-
sion and transmis-
sion ground.
8 CHECK POOR CONTACT IN CONNECTORS.Is there poor contact in control
module power supply, ground
line and data link connector?Repair the con-
nector.Replace the TCM.
Transmission Con-
trol Module
(TCM).>