SUBARU FORESTER 2004 Service Repair Manual

4AT(H4DOTC)-5
AUTOMATIC TRANSMISSION (DIAGNOSTIC)
General Description
3. General Description
A: CAUTION
Supplemental Restraint System “Airbag”
The airbag system wiring harness is routed near
the TCM.
CAUTION:
 All airbag system wiring harness and con-
nectors are colored yellow. Do not use an elec-
trical test equipment on these circuit.
 Be careful not to damage the airbag system
wiring harness when performing diagnostics and
servicing the TCM.
Measurement
When measuring the voltage and resistance of
ECM, TCM or each sensor, use a tapered pin with
diameter of less than 0.64 mm (0.025 in) in order to
avoid poor contact. Do not insert the pin more than
0.65 mm (0.026 in).
B: INSPECTION
1. BATTERY
Measure the battery voltage and specific gravity of
electrolyte.
Standard voltage: 12 V or more
Specific gravity: Above 1.260
2. TRANSMISSION GROUND
Make sure that the ground terminal bolt is tightened
securely.
Chassis side
Tightening torque:
13 N
⋅m (1.3 kgf-m, 9.4 ft-lb)
3. ATF LEVEL
Make sure that ATF level is in the specification. <Ref.
to 4AT-30, INSPECTION, Automatic Transmission
Fluid.>
4. FRONT DIFFERENTIAL OIL LEVEL
Make sure that front differential oil level is in the spec-
ification. <Ref. to 4AT-31, INSPECTION, Differential
Gear Oil.>
AT-00412
(A) Level gauge
(B) “HOT” side
(C) Upper level
(D) Lower level
(E) “COLD” side
(A) Upper level
(B) Lower level
PI-00105
COLD
LFHOT LF
(A)
(C)
(D)
(C)
(D)
(E)
(B)
AT-00317
(A)
(B)
LF

4AT(H4DOTC)-6
AUTOMATIC TRANSMISSION (DIAGNOSTIC)
General Description
5. OPERATION OF SELECT LEVER
Make sure there is no abnormal noise, dragging or
contact pattern in each select lever range.
WARNING:
Stop the engine while checking operation of se-
lect lever.
6. POWER SWITCH
Make sure that the POWER indicator light in com-
bination meter comes on, when turning the POW-
ER switch to ON.
7. HOLD SWITCH
Make sure that the HOLD indicator light in combina-
tion meter comes on, when turning the HOLD switch
to ON.
AT-00413
P
R
N
D
3
2
1
AT-00319
AT-00320

4AT(H4DOTC)-7
AUTOMATIC TRANSMISSION (DIAGNOSTIC)
General Description
C: PREPARATION TOOL
1. SPECIAL TOOL
2. GENERAL TOOL
ILLUSTRATION TOOL NUMBER DESCRIPTION REMARKS
24082AA230
(Newly adopted tool)CARTRIDGE Troubleshooting for electrical system.
22771AA030 SUBARU SELECT
MONITOR KITTroubleshooting for electrical system.
 English: 22771AA030 (Without printer)
 German: 22771AA070 (Without printer)
 French: 22771AA080 (Without printer)
 Spanish: 22771AA090 (Without printer)
TOOL NAME REMARKS
Circuit tester Used for measuring resistance, voltage and current.
Oscilloscope Used for measuring sensor.
ST24082AA230
ST22771AA030

4AT(H4DOTC)-8
AUTOMATIC TRANSMISSION (DIAGNOSTIC)
Electrical Components Location
4. Electrical Components Location
A: LOCATION
1. CONTROL MODULE
 LHD MODEL
 RHD MODEL
(1) Engine control module (ECM) (3) Transmission control module
(TCM)(4) Data link connector
(2) AT diagnostic warning light
(POWER indicator light)
AT-00414
(1) (2)
(3) (4)
AT-00369 (2)
(4)
(1)
(3)

4AT(H4DOTC)-9
AUTOMATIC TRANSMISSION (DIAGNOSTIC)
Electrical Components Location
LHD RHD
AT-00323
(1)
AT-00324
(2)
(3)
AT-00416
(3)
AT-00372
(4)
AT-00417

4AT(H4DOTC)-10
AUTOMATIC TRANSMISSION (DIAGNOSTIC)
Electrical Components Location
2. SENSOR
(1) Throttle position sensor (2.0 L
model)(4) Rear vehicle speed sensor (7) Accelerator pedal position sensor
(2.5 L model)
(5) Torque converter turbine speed
sensor (2) Front vehicle speed sensor
(3) Inhibitor switch (6) ATF temperature sensor
AT-01836
(3) (6)
(5) (1) (2) (4)(7)
(1)
AT-01105
AT-01474
(2)(4)
(3)AT-00330
(5)
AT-00331

4AT(H4DOTC)-11
AUTOMATIC TRANSMISSION (DIAGNOSTIC)
Electrical Components Location
3. SOLENOID
(1) Line pressure linear solenoid (4) Low clutch duty solenoid (7) Lock-up duty solenoid
(2) High clutch duty solenoid (5) Transfer duty solenoid
(3) 2-4 brake duty solenoid (6) Low & reverse duty solenoid
(6)
AT-00378
(7)
AT-01837
AT-00379
(1)(2)(3)(4)
(5)(6)
(7)
(2) (3) (4)
(7) (6) (5)
(1)
AT-00380

4AT(H4DOTC)-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.
ItemConnector
No.Terminal No. Measuring conditions Voltage (V)Resistance
to chassis
ground (Ω)
Back-up power supply B5627
Ignition switch OFF 10 — 13 — 28
29
ACC power supply B56 16 Ignition switch ACC 10 — 13 —
Ignition power supplyB56 21
Ignition switch ON
(with engine OFF)10 — 13 —
B56 31
Inhibitor
switch“P” range
switchB55 5Select lever in “P” range Less than 1
—
Select lever in any other than
“P” range (except “N” range)More than 8
“N” range
switchB55 22Select lever in “N” range Less than 1
—
Select lever in any other
than “N” rangeMore than 8
“R” range
switchB55 14Select 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
switchB54 16Select lever in “3” range Less than 1
—
Select lever in any other
than “3” rangeMore than 8
“2” range
switchB54 4Select lever in “2” range Less than 1
—
Select lever in any other
than “2” rangeMore than 8
“1” range
switchB54 10Select lever in “1” range Less than 1
—
Select lever in any other
than “1” rangeMore than 8
Brake switch B55 20Brake pedal depressed. More than 10.5
—
Brake pedal released. Less than 1
AT-01107
B54B55B56
1 2 7
8 9 5 6
3 4
10 11 12
19 20 21 13 14 15 16
17 18 22 23
241 2 7 8 95634
10 11 12 19 20 21
29 30 3113 14 15 16 17
27
28 18
22 23 24 25 26 1 2 3
8 9 104
11 12
13 14 15
165 6
7
17To
ToTo

4AT(H4DOTC)-13
AUTOMATIC TRANSMISSION (DIAGNOSTIC)
Transmission Control Module (TCM) I/O Signal
Accelerator pedal position
sensor (2.5 L model)
B55 19Throttle fully closed. More than 0.2
—
Throttle position sensor (2.0
L model)Throttle fully open. Less than 4.6
Accelerator pedal position
sensor power supply (2.5 L
model)B55 10 Ignition switch ON
(with engine OFF)Approx. 5 —
Throttle position sensor
power supply (2.0 L model)
ATF temperature sensor B55 21ATF temperature 20°C
(68°F)3.5 — 4.3 3.9 k — 4.7 k
ATF temperature 80°C
(176°F)1.5 — 1.9 500 — 600
Rear vehicle speed sensor B55 24Vehicle speed at least
20 km/h (12 MPH)More than 2 (AC range) —
Front vehicle speed sensor B55 6Vehicle stopped. 0
450 — 750
Vehicle speed at least
20 km/h (12 MPH)More than 1 (AC range)
Torque converter turbine
speed sensorB55 7Engine idling after warm-
up. (“D” range)0
450 — 750
Engine idling after warm-
up. (“N” range)More than 1 (AC range)
Vehicle speed output signal B56 1Vehicle speed at least
10 km/h (6 MPH)Less than 1←
→More than 4—
Engine speed signal B55 13Ignition switch ON
(with engine OFF)Less than 1
—
Ignition switch ON
(with engine ON)More than 5
(AC range)
Line pressure linear solenoid B56 20Ignition switch ON
(with engine OFF)
“R” range and throttle fully
closed after warm-up.5 — 7
4.0 — 8.0
Ignition switch ON
(with engine OFF)
“R” range and throttle fully
open after warm-up.3 — 5
Lock-up duty solenoid B56 5When lock up occurs. More than 10.5
2.0 — 4.5
When lock up is released. Less than 1
Transfer duty solenoid B56 4“P” or “N” range Less than 1
2.0 — 4.5
Throttle fully open and with
select lever in 1st gear.More than 10.5
2-4 brake duty solenoid B56 6“P” or “N” range More than 10.5
2.0 — 4.5
2nd or 4th gear Less than 1
High clutch duty solenoid B56 83rd or 4th gear Less than 1
2.0 — 4.5
“P” or “N” range More than 10.5
Low clutch duty solenoid B56 91st or 2nd gear Less than 1
2.0 — 4.5
“P” or “N” range More than 10.5
Low & reverse duty solenoid B56 7“P” or “N” range More than 10.5
2.0 — 4.5
“1” range More than 5
HOLD switch B54 2HOLD switch ON Less than 1
—
HOLD switch OFF More than 10.5 Check with ignition switch ON.
ItemConnector
No.Terminal No. Measuring conditions Voltage (V)Resistance
to chassis
ground (Ω)

4AT(H4DOTC)-14
AUTOMATIC TRANSMISSION (DIAGNOSTIC)
Transmission Control Module (TCM) I/O Signal
POWER switch B54 8POWER switch ON Less than 1
—
POWER switch OFF More than 8
POWER indicator light B56 25Light ON Less than 1
—
Light OFF More than 9
ABS signal B54 12ABS switch ON Less than 1
—
ABS switch OFF 6.5 — 15
Front vehicle speed sensor
groundB55 15 — 0 Less than 1
Rear vehicle speed sensor
groundB55 23 — 0 Less than 1
Combination meter B54 6 Ignition switch ON Pulse signal —
System ground lineB55 17
— 0 Less than 1 B56 2
B56 3
B55 8
Sensor ground line 3 B55 9 — 0 Less than 1
Sensor ground line 4 B56 19 — 0 Less than 1
Range lock signal B56 18“D” range 0 km/h (0 MPH) More than 10.5
20 — 40
“D” range 20 km/h
(12 MPH)Less than 1
Data link signal (Subaru
Select Monitor)B56 12 — — —
CAN communication signal
(+)B55 3 Ignition switch ON Pulse signal —
CAN communication signal
(−)B55 12 Ignition switch ON Pulse signal —Check with ignition switch ON.
ItemConnector
No.Terminal No. Measuring conditions Voltage (V)Resistance
to chassis
ground (Ω)