2004 SUBARU FORESTER ignition

4AT-78
AUTOMATIC TRANSMISSION
Dropping Resistor
23.Dropping Resistor
A: REMOVAL
1) Disconnect the ground cable from battery.
2) Disconnect the connector from dropping resis-
tor.
3) Remove the dropping resistor.
B: INSTALLATION
Install in the reverse order of removal.
Tightening torque:
6.4 N
⋅m (0.65 kgf-m, 4.7 ft-lb)
C: INSPECTION
(A) Dropping resistor
AT-00041
AT-00313
(A)
(A) Dropping resistor
AT-00313
(A)
Step Check Yes No
1 CHECK RESISTOR.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from dropping
resistor.
3) Measure the resistance between dropping
resistors.
Te r m i n a l s
No. 1 — No. 2:Is the resistance 9 — 15 Ω? Go to step 2.Replace the drop-
ping resistor. to 4AT-78, Drop-
ping Resistor.>
2 CHECK RESISTOR.
Measure the resistance between dropping
resistors.
Te r m i n a l s
No. 3 — No. 4:Is the resistance 9 — 15 Ω? Dropping resistor
is normal.Replace the drop-
ping resistor. to 4AT-78, Drop-
ping Resistor.>

4AT(H4SO)-2
AUTOMATIC TRANSMISSION (DIAGNOSTIC)
Basic Diagnostic Procedure
1. Basic Diagnostic Procedure
A: PROCEDURE
Step Check Yes No
1 CHECK PRE-INSPECTION.
1) Ask the customer when and how trouble
occurred using interview checklist. 4AT(H4SO)-4, Check List for Interview.>
2) Before performing the diagnosis, inspect
following items which might influence the AT
problems.
 General inspection INSPECTION, General Description.>
 Disconnection of harness connector
 Visually check the damage of harness
 Oil leak
 Stall speed test
 Line pressure test Pressure Test.>
 Transfer clutch pressure test 38, Transfer Clutch Pressure Test.>
 Time lag test Te s t . >
 Road test
 Inhibitor switch Switch.>Is the unit that might influence
AT problem normal?Go to step 2.Repair or replace
each item.
2 CHECK POWER INDICATOR LIGHT.
Turn the ignition switch to ON.Does the POWER indicator
light illuminate?Go to step 4.Go to step 3.
3 CHECK POWER INDICATOR LIGHT.
1) Turn the ignition switch to OFF.
2) Repair the POWER indicator light circuit or
power supply and ground line circuit.
Indicator Light Display.>
3) Turn the ignition switch to ON.Is the POWER indicator light
illuminate?Go to step 4.Go to step 5.
4 CHECK INDICATION OF DTC.
Calling up the DTC.
Without Subaru Select Monitor
SELECT MONITOR, OPERATION, Read
Diagnostic Trouble Code (DTC).>
With Subaru Select Monitor
SELECT MONITOR, OPERATION, Read
Diagnostic Trouble Code (DTC).>
NOTE:
If the communication function of select monitor
cannot be executed normally, check the communi-
cation circuit. NICATION FOR INITIALIZING IMPOSSIBLE,
Diagnostic Procedure for Subaru Select Monitor
Communication.>Is the DTC displayed? Go to step 6.
NOTE:
Record all DTC.Go to step 5.

4AT(H4SO)-12
AUTOMATIC TRANSMISSION (DIAGNOSTIC)
Transmission Control Module (TCM) I/O Signal
5. Transmission Control Module (TCM) I/O Signal
A: ELECTRICAL SPECIFICATION
Check with ignition switch ON.
ContentConnector
No.Terminal No. Measuring conditions Voltage (V)Resistance
to chassis
ground (Ω)
Back-up power supply B56 1 Ignition switch OFF 10 — 13 —
Ignition power supplyB54 23
Ignition switch ON (with
engine OFF)10 — 13 —
B54 24
Inhibitor
switch“P” range
switchB55 1Select lever in “P” range Less than 1
—
Select lever in any other than
“P” range (except “N” range)More than 8
“N” range
switchB55 14Select lever in “N” range Less than 1
—
Select lever in any other than
“N” range (except “P” range)More than 8
“R” range
switchB55 3Select lever in “R” range Less than 1
—
Select lever in any other
than “R” rangeMore than 8
“D” range
switchB55 4Select lever in “D” range Less than 1
—
Select lever in any other
than “D” rangeMore than 8
“3” range
switchB55 5Select lever in “3” range Less than 1
—
Select lever in any other
than “3” rangeMore than 8
AT-00568
toB54
1 2
7 8 9563 4
10 11 12
19 20 21 13 14 15 16 17 18
22
23
24
toB55
1 2 3 4
10 11 12
19 20 21 13
5 6
14 15
7 8 9
16 17 18
22 23 24
toB56
1 2
7 8 95 63 4
10 11 12
19 20 21 13 14 15
16 17 18
22
23
24

4AT(H4SO)-13
AUTOMATIC TRANSMISSION (DIAGNOSTIC)
Transmission Control Module (TCM) I/O Signal
Inhibitor
switch“2” range
switchB55 6Select lever in “2” range Less than 1
—
Select lever in any other
than “2” rangeMore than 8
“1” range
switchB55 7Select lever in “1” range Less than 1
—
Select lever in any other
than “1” rangeMore than 8
Brake switch B55 12Brake pedal depressed More than 10.5
—
Brake pedal released Less than 1
Kick-down switch B55 11Throttle fully opened Less than 1
—
Throttle fully closed More than 6.5
AT OIL TEMP warning light B56 10Light ON Less than 1
—
Light OFF More than 9
Throttle position sensor B54 3Throttle fully closed 0.2 — 1.0
—
Throttle fully open 4.2 — 4.7
Throttle position sensor
power supplyB54 2Ignition switch ON (with
engine OFF)4.8 — 5.3 —
ATF temperature sensor B54 11ATF temperature 20°C
(68°F)1.6 — 2.0 2.1 k — 2.9 k
ATF temperature 80°C
(176°F)0.4 — 0.9 275 — 375
Rear vehicle speed sensor B55 24Vehicle stopped 0
450 — 650
Vehicle speed at least 20
km/h (12 MPH)More than 1 (AC range)
Front vehicle speed sensor B55 18Vehicle stopped 0
450 — 650
Vehicle speed at least 20
km/h (12 MPH)More than 1 (AC range)
Torque converter turbine
speed sensorB55 8Engine idling after warm-
up (D range)0
450 — 650
Engine idling after warm-
up (N range)More than 1 (AC range)
Vehicle speed output signal B56 17Vehicle speed at most 10
km/h (6 MPH)Less than 1 ←
→ More than 4—
Engine speed signal B55 17Ignition switch ON (with
engine OFF)More than 10.5
—
Ignition switch ON (with
engine ON)8 — 11
Cruise set signal B55 22When cruise control is set
(SET lamp ON)Less than 1
—
When cruise control is not
set (SET lamp OFF)More than 6.5
Torque control signal 1 B56 5Ignition switch ON (with
engine ON)More than 4 —
Torque control signal 2 B56 14Ignition switch ON (with
engine ON)More than 4 —
Torque control cut signal B55 10Ignition switch ON
(After engine is warmed-up)8—
Intake manifold pressure
signalB54 1 Engine idling after warm-up 0.4 — 1.6 —
Shift solenoid 1 B54 221st or 4th gear More than 9
10 — 16
2nd or 3rd gear Less than 1
Shift solenoid 2 B54 51st or 2nd gear More than 9
10 — 16
3rd or 4th gear Less than 1 Check with ignition switch ON.
ContentConnector
No.Terminal No. Measuring conditions Voltage (V)Resistance
to chassis
ground (Ω)

4AT(H4SO)-14
AUTOMATIC TRANSMISSION (DIAGNOSTIC)
Transmission Control Module (TCM) I/O Signal
Line pressure duty solenoid B54 9Ignition switch ON (with
engine OFF)
Throttle fully closed after
war m-up1.5 — 4.0
2.0 — 4.5
Ignition switch ON (with
engine OFF)
Throttle fully open after
war m-upLess than 0.5
Lock-up duty solenoid B54 7When lock up occurs More than 8.5
10 — 17
When lock up is released Less than 0.5
Transfer duty solenoid B54 6Fuse on FWD switch Less than 0.5
10 — 17 Fuse removed from FWD
switch (with throttle fully
open and with select lever
in 1st gear)More than 8.5
2-4 brake duty solenoid B54 18Throttle fully closed (with
engine OFF) after warm-up1.5 — 5.0
2.0 — 4.5
Throttle fully open (with
engine OFF) after warm-upLess than 0.5
2-4 brake timing solenoid B54 161st gear Less than 1
10 — 16
3rd gear More than 9
Low clutch timing solenoid B54 152nd gear Less than 1
10 — 16
4th gear More than 9
HOLD switch B55 16HOLD switch ON Less than 1 —
HOLD switch OFF More than 8 —
POWER switch B55 23POWER switch ON Less than 1 —
POWER switch OFF More than 10 —
POWER indicator light B56 11Light ON Less than 1 —
Light OFF More than 9 —
FWD switch B55 20Fuse removed 6 — 9.1 —
Fuse installed Less than 1 —
FWD indicator light B56 2Fused on FWD switch Less than 1 —
Fuse removed from FWD
switchMore than 9 —
ABS signal B55 21ABS switch ON Less than 1 —
ABS switch OFF 6.5 — 15 —
Sensor ground line 1 B54 20 — 0 Less than 1
Sensor ground line 2 B55 9 — 0 Less than 1
System ground lineB56 19
— 0 Less than 1
B54 21
Sensor ground line 3 B54 10 — 0 Less than 1
Sensor ground line 4 B54 19 — 0 Less than 1
AT diagnosis signal B56 21 Ignition switch ONLess than 1 ←
→ More than 4—
Data link signal (Subaru
Select Monitor)B56 15 — — —Check with ignition switch ON.
ContentConnector
No.Terminal No. Measuring conditions Voltage (V)Resistance
to chassis
ground (Ω)

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)-19
AUTOMATIC TRANSMISSION (DIAGNOSTIC)
Subaru Select Monitor
3. CLEAR MEMORY MODE
1) On the «Main Menu» display screen, select the
{2. 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 {Clear Memory} and press the [YES] key.
5) When the “Done” and “Turn Ignition Switch OFF”
are shown on display screen, turn the Subaru Se-
lect Monitor and ignition switch to OFF.
NOTE:
For detailed operation procedure, refer to the SUB-
ARU SELECT MONITOR OPERATION MANUAL.