ESP SUBARU FORESTER 2004 Service Workshop Manual

EN(H4DOTC)-147
ENGINE (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
AD:DTC P0139 O2 SENSOR CIRCUIT SLOW RESPONSE (BANK 1 SENSOR 2)
DTC DETECTING CONDITION:
Two consecutive driving cycles with fault
CAUTION:
After repair or replacement of faulty parts, conduct Clear Memory Mode ERATION, Clear Memory Mode.> and Inspection Mode .
WIRING DIAGRAM:
MAIN RELAY
B47 1 2 3 5 4 6
E
T5
*1
*2 B18
3
B122
1
3
T6 REAR
OXYGEN SENSOR
A6
A7D31
C35
ECMB135
B136 B :
B134 A :
C :
1
4
B83
B2 D25
B137D :
EN-02321
: LHD
: RHD34
12
56
B21
B134
B135
F60
B83
B47T6
B1361
23456
F2
2143
LHD : 5
RHD : 4
LHD : 1
RHD : 1*1
*2
BATTERY
B100F2 14LHD
RHD
LHD
RHD LHD
RHD
LHD
RHD 4
6
E
B100
F2
F60
E3
20 3
RHD
LHD
RHD
: LHD
B21: RHD
LHD
: LHDE2
: RHD
B18
B122
B137
2345 678911 12 13 14 17 18 19 201101516
567
82 1
94 310
22 23 11 12 13 14 15
24 25
2616 17
18 19 20 21
27 28 29 30 31
56
782 1
94 310
24 22 23 2511 12 13
1415
26 27
2816
17 18 19 20 21
33 34 29
32 30
31 35
12345678
567
82 1
94 310
24 22 23 2511 12 13 14 15
26 27
2816 17 18 19
20 21
29 30 31 32 33 34 35
123
4
56
78
9
1011 12
1314 15 16
1234
4
22
T5
B18
56 7
82 1
94 310
24 22 23 25 11 12 13 14 15
26 27
2816 17
18 19 20 21
33 34 29
32 30 31

FU(H4DOTC 2.5)-63
FUEL INJECTION (FUEL SYSTEM)
Fuel System Trouble in General
31.Fuel System Trouble in General
A: INSPECTION
NOTE:
 When the vehicle is left unattended for an extended period of time, water may accumulate in the fuel tank.
To prevent water condensation.
(1) Top off the fuel tank or drain the fuel completely.
(2) Drain the water condensation from the fuel filter.
 Refilling the fuel tank.
Refill the fuel tank while there is still some fuel left in the tank.
 Protecting the fuel system against freezing and water condensation.
(3) Cold areas:
In snow-covered areas, mountainous areas, skiing areas, etc. where ambient temperatures drop below
0°C (32°F) throughout the winter season, use an anti-freeze solution in the cooling system. Refueling will
also complement the effect of anti-freeze solution each time the fuel level drops to about one-half. After
the winter season, drain the water which may have accumulated in the fuel filter and fuel tank in the man-
ner same as that described under “Affected areas” below.
(4) Affected areas:
When the water condensation is notched in the fuel filter, drain the water from both the fuel filter and fuel
tank or use a water removing agent (or anti-freeze solution) in the fuel tank.
 Observe the instructions, notes, etc., indicated on the label affixed to the anti-freeze solution (water remov-
ing agent) container before use.
Trouble and possible cause Corrective action
1. Insufficient fuel supply to the injector
1) Fuel pump will not operate.
❍Defective terminal contact.Inspect connections, especially ground, and tighten
securely.
❍Trouble in electromagnetic or electronic circuit parts. Replace the fuel pump.
2) Lowering of fuel pump function. Replace the fuel pump.
3) Clogged dust or water in the fuel filter. Replace the fuel filter, clean or replace fuel tank.
4) Clogged or bent fuel pipe or hose. Clean, correct or replace the fuel pipe or hose.
5) Air is mixed in the fuel system. Inspect or retighten each connection part.
6) Clogged or bent breather tube or pipe. Clean, correct or replace the air breather tube or pipe.
7) Damaged diaphragm of pressure regulator. Replace.
2. Leakage or blow out fuel
1) Loosened joints of the fuel pipe. Retightening.
2) Cracked fuel pipe, hose and fuel tank. Replace.
3) Defective welding part on the fuel tank. Replace.
4) Defective drain packing of the fuel tank. Replace.
5) Clogged or bent air breather tube or air vent tube.Clean, correct or replace the air breather tube or air vent
tube.
3. Gasoline smell inside of compartment
1)Loose joints at air breather tube, air vent tube and fuel filler
pipe.Retightening.
2) Defective packing air tightness on the fuel saucer. Correct or replace the packing.
3) Cracked fuel separator. Replace the separator.
4) Inoperative fuel pump modulator or circuit. Replace.
4. Defective fuel meter indicator
1) Defective operation of fuel level sensor. Replace.
2) Defective operation of fuel meter. Replace.
5. Noise
1) Large operation noise or vibration of fuel pump. Replace.

4AT-117
AUTOMATIC TRANSMISSION
Front Differential
37.Front Differential
A: REMOVAL
1) Remove the transmission assembly from vehi-
cle. mission Assembly.>
2) Pull out the torque converter clutch assembly.
Clutch Assembly.>
3) Remove the input shaft.
4) Lift-up the lever on rear side of transmission har-
ness connector, and then disconnect it from the
stay.
5) Disconnect the inhibitor switch from the stay.
6) Remove the ATF charger pipe. REMOVAL, Oil Charger Pipe.>
7) Remove the ATF cooler inlet and outlet pipes.
Hose.>
8) Separate the torque converter clutch case and
transmission case. Torque Converter Clutch Case.>
9) Remove the seal pipe.
10) Remove the differential side retainers using
ST.
NOTE:
Hold the differential case assembly by hand to
avoid damaging retainer mounting hole of torque
converter clutch case.
ST 499787000 WRENCH ASSY
11) Remove the differential assembly without dam-
aging installation part of retainer.
B: INSTALLATION
1) Install the differential assembly to torque con-
verter clutch case.
CAUTION:
Do not damage the inside of torque converter
clutch case (especially the mating surface of
differential side retainer).
2) Install the O-ring to left and right differential side
retainer.
3) Install the side retainers using ST. 117, REMOVAL, Front Differential.>
ST 499787000 WRENCH ASSY
4) Adjust the front differential backlash. 4AT-121, ADJUSTMENT, Front Differential.>
5) Install the lock plate.
Tightening torque:
25 N
⋅m (2.5 kgf-m, 18.1 ft-lb)
AT-00114(A) Differential ASSY
(A) Lock plate
AT-00215
(A)
AT-00214
(A)

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)-21
AUTOMATIC TRANSMISSION (DIAGNOSTIC)
Read Diagnostic Trouble Code (DTC)
 The way of reading Diagnostic Trouble Code (DTC)
The POWER indicator light flashes the code corresponding to faulty part.
The long segment (1.2 sec on) indicates a “ten”, and the short segment (0.2 sec on) signifies a “one”.
2. WITH SUBARU SELECT MONITOR
Refer to Subaru Select Monitor for information about how to obtain and understand DTC. 17, OPERATION, Subaru Select Monitor.>
(1) Normal code (3) DTC 11 and 23 (4) Unit: Seconds
(2) DTC 11
AT-01305
0.25
1.2 1.50.3
0.2
ON
OFF (1)
ON
OFF
1.2 1.50.3
0.2
ON
OFF
1.2
0.3
1.2
0.3 0.3 0.30.2 0.2 0.2
(2)
(3)
(4)

4AT(H4SO)-43
AUTOMATIC TRANSMISSION (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
9 CHECK HARNESS CONNECTOR BETWEEN
TCM AND ECM.
Measure the resistance of harness between
TCM and ECM connector.
Connector & terminal
(B54) No. 3 — (B135) No. 13:Is the resistance less than 1
Ω?Go to step 10.Repair the open
circuit in harness
between TCM and
ECM connector.
10 CHECK HARNESS CONNECTOR BETWEEN
TCM AND ECM.
Measure the resistance of harness between
TCM and ECM connector.
Connector & terminal
(B54) No. 2 — (B135) No. 19:Is the resistance less than 1
Ω?Go to step 11.Repair the open
circuit in harness
between TCM and
ECM connector.
11 PREPARE SUBARU SELECT MONITOR.Do you have a Subaru Select
Monitor?Go to step 14.Go to step 12.
12 CHECK INPUT SIGNAL FOR TCM.
1) Connect the connectors to TCM, throttle
position sensor and ECM.
2) Turn the ignition switch to ON (engine
OFF).
3) Close the throttle completely.
4) Measure the voltage between TCM con-
nector and chassis ground.
Connector & terminal
(B54) No. 3 (+) — Chassis ground (
−):Is the voltage 0.2 — 1.0 V? Go to step 13.Go to step 18.
13 CHECK INPUT SIGNAL FOR TCM.
1) Open the throttle completely.
2) Measure the voltage between TCM con-
nector and chassis ground.
Connector & terminal
(B54) No. 3 (+) — Chassis ground (
−):Is the voltage 4.2 — 4.7 V? Go to step 16.Go to step 18.
14 CHECK INPUT SIGNAL FOR TCM USING
SUBARU SELECT MONITOR.
1) Connect the connectors to TCM, throttle
position sensor and ECM.
2) Connect the Subaru Select Monitor to data
link connector.
3) Turn the ignition switch to ON (engine
OFF).
4) Turn the Subaru Select Monitor switch to
ON.
5) Throttle fully closed.
6) Read the data of throttle position sensor
using Subaru Select Monitor.
 Throttle position sensor input signal is indi-
cated.Is the value voltage 0.2 — 1.0
V?Go to step 15.Go to step 18.
15 CHECK INPUT SIGNAL FOR TCM USING
SUBARU SELECT MONITOR.
Throttle fully open.
N
OTE:
Must be changed correspondingly with the ac-
celerator pedal operation (from “released” to
“depressed” position).Is the value voltage 4.2 — 4.7
V?Go to step 17.Go to step 18. Step Check Yes No

4AT(H4DOTC)-62
AUTOMATIC TRANSMISSION (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
M: DTC P0736 REVERSE INCORRECT RATIO
DTC DETECTING CONDITION:
Vehicle speed sensor malfunction and torque converter turbine speed sensor malfunction, etc. or control
valve malfunction.
TROUBLE SYMPTOM:
 Shift point is too high or too low.
 Excessive shift shock.
 Tight corner “braking” phenomenon.
 Gear is not shifted to reverse.
 Gear position is held by fail safe function.
Step Check Yes No
1 PREPARE SUBARU SELECT MONITOR.Do you have a Subaru Select
Monitor?Go to step 2.Go to step 5.
2 CHECK ACCELERATOR PEDAL POSITION
SENSOR.
1) Connect the Subaru Select Monitor to data
link connector.
2) Turn the ignition switch to ON.
3) Read the value of accelerator pedal posi-
tion sensor on Subaru Select Monitor.Does the value of accelerator
pedal position sensor change
from 0% to 100% smoothly
when throttle was operated from
fully closing to fully opening?Go to step 3.Check accelerator
pedal position sen-
sor. 4AT(H4DOTC)-94,
DTC P1708
THROTTLE POSI-
TION SENSOR
CIRCUIT LOW
INPUT, Diagnostic
Procedure with
Diagnostic Trou-
ble Code (DTC).>
3 CHECK FRONT VEHICLE SPEED SENSOR.
1) Lift-up the vehicle and place rigid racks.
2) Start the engine.
3) Move the select lever “D” range and slowly
increase vehicle speed.
NOTE:
The speed difference between front and rear
wheels may light ABS warning light, but this indi-
cates no malfunction. When AT control diagnosis
is finished, perform the ABS memory clearance
procedure of on-board diagnostics system.Does the vehicle speed dis-
played by Subaru Select Moni-
tor almost correspond with
vehicle speed indicated by
combination meter?Go to step 4.Check the front
vehicle speed sen-
sor.
4 CHECK TORQUE CONVERTER TURBINE
SPEED SENSOR.
1) Move the select lever to “P” or “N” range.
2) Idle the engine.Does the turbine speed sen-
sor revolution displayed by
Subaru Select Monitor almost
correspond with engine revolu-
tion indicated by tachometer?There are mal-
functions in TCM,
TCM connector
poor contact or
transmission
assembly mechan-
ical malfunction.Check the torque
converter turbine
speed sensor cir-
cuit.
5 CHECK ACCELERATOR PEDAL POSITION
SENSOR.
1) Turn the ignition switch to ON.
2) Fully close the throttle.
3) Measure the voltage between TCM and
chassis ground.
Connector & terminal
(B55) No. 19 (+) — Chassis ground (
−):Is the voltage 0.8 — 1.2 V? Go to step 6.Check the acceler-
ator pedal position
sensor circuit.
4AT(H4DOTC)-94,
DTC P1708
THROTTLE POSI-
TION SENSOR
CIRCUIT LOW
INPUT, Diagnostic
Procedure with
Diagnostic Trou-
ble Code (DTC).>

4AT(H4DOTC)-64
AUTOMATIC TRANSMISSION (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
N: DTC P0741 TORQUE CONVERTER CLUTCH CIRCUIT PERFORMANCE OR
STUCK OFF
DTC DETECTING CONDITION:
 Lock up clutch malfunction
 Locking of valve
TROUBLE SYMPTOM:
Lock up is not operated.
Step Check Yes No
1 CHECK LOCK UP DUTY SOLENOID CIR-
CUIT.
Check according as DTC P0743 procedure.Is there malfunction? Repair or replace
the lock up duty
solenoid circuit.Go to step 2.
2 CHECK INHIBITOR SWITCH CIRCUIT.
Check according as DTC P0705 procedure.Is there malfunction? Repair or replace
the inhibitor switch
circuit.Go to step 3.
3 CHECK STOP LIGHT SWITCH CIRCUIT.
Check according as DTC P0719 and DTC
P0724 procedure.Is there malfunction? Repair or replace
the stop light
switch circuit.Go to step 4.
4 CHECK ATF TEMPERATURE SENSOR CIR-
CUIT.
Check according to DTC P0712 and DTC
P0713 procedure.Is there malfunction? Repair or replace
the ATF tempera-
ture sensor circuit.Go to step 5.
5 PREPARE SUBARU SELECT MONITOR.Do you have a Subaru Select
Monitor?Go to step 6.Go to step 9.
6 CHECK ACCELERATOR PEDAL POSITION
SENSOR.
1) Connect the Subaru Select Monitor to data
link connector.
2) Turn the ignition switch to ON.
3) Read the value of accelerator pedal posi-
tion sensor on Subaru Select Monitor display.Does the value of accelerator
pedal position sensor change
from 0% to 100% smoothly
when throttle was operated from
fully closing to fully opening?Go to step 7.Check the acceler-
ator pedal position
sensor circuit.
7 CHECK TORQUE CONVERTER TURBINE
SPEED SENSOR.
1) Move the select lever to “P” or “N” range.
2) Idle the engine.Does the turbine revolution dis-
played by Subaru Select Moni-
tor almost correspond with
engine revolution indicated by
tachometer?Go to step 8.Check the torque
converter turbine
speed sensor cir-
cuit.
8 CHECK ENGINE SPEED SIGNAL.
Idle the engine.Does the turbine revolution dis-
played by Subaru Select Moni-
tor almost correspond with
engine revolution indicated by
tachometer?There is malfunc-
tion in TCM, TCM
connector poor
contact or trans-
mission assembly
mechanical mal-
fuction.Check the engine
speed signal cir-
cuit.
9 CHECK ACCELERATOR PEDAL POSITION
SENSOR.
Check according to DTC P1708, DTC 1709
and DTC P1714 procedure.Is there a malfunction? Go to step 10.Repair or replace
the accelerator
pedal position sen-
sor circuit.
10 CHECK TORQUE CONVERTER TURBINE
SPEED SENSOR.
Check according to DTC P0715 procedure.Is there a malfunction? Go to step 11.Repair or replace
the torque converter
turbine speed sen-
sor circuit.
11 CHECK ENGINE SPEED SIGNAL.
Check according to DTC P0725 procedure.Is there a malfunction? Repair or replace
the engine speed
signal circuit. There is malfunc-
tion in TCM, TCM
connector poor
contact or trans-
mission assembly
mechanical mal-
function.

5MT-111
MANUAL TRANSMISSION AND DIFFERENTIAL
General Diagnostic
26.General Diagnostic
A: INSPECTION
1. MANUAL TRANSMISSION
Symptom Possible cause Remedy
1. Gears are difficult to intermesh.
N
OTE:
The cause for difficulty in shifting gears
can be classified into two kinds: one is
malfunction of the gear shift system and
the other is malfunction of the transmis-
sion. However, if the operation is heavy
and engagement of the gears is difficult,
defective clutch disengagement may also
be responsible. Check whether the clutch
is correctly functioning, before checking
the gear shift system and transmission.(a) Worn, damaged or burred chamfer of
internal spline of sleeve and reverse
driven gearReplace.
(b) Worn, damaged or burred chamfer of
spline of gearsReplace.
(c) Worn or scratched bushings Replace.
(d) Incorrect contact between synchro-
nizer ring and gear cone or wear Correct or replace.
2. Gear slips out.
 Gear slips out when coasting on rough
road.
 Gear slips out during acceleration.(a) Defective pitching stopper adjustment Adjust.
(b) Loose engine mounting bolts Tighten or replace.
(c) Worn fork shifter, broken shifter fork
rail springReplace.
(d) Worn or damaged ball bearing Replace.
(e) Excessive clearance between splines
of synchronizer hub and synchronizer
sleeveReplace.
(f) Worn tooth step of synchronizer hub Replace.
(g) Worn 1st driven gear and driven shaft Replace.
(h) Worn 2nd driven gear and 2nd bush Replace.
(i) Worn reverse idler gear and bushing Replace.
3. Unusual noise comes from transmis-
sion.
N
OTE:
If an unusual noise is heard when the ve-
hicle is parked with its engine idling and if
the noise ceases when the clutch is disen-
gaged, it may be considered that the
noise comes from the transmission.(a) Insufficient or improper lubrication Lubricate or replace with specified oil.
(b) Worn or damaged gears and bearings
NOTE:
If the trouble is only wear of the tooth sur-
faces, merely a high roaring noise will oc-
cur at high speeds, but if any part is
broken, rhythmical knocking sound will be
heard even at low speeds.Replace.

CL-42
CLUTCH SYSTEM
General Diagnostic Table
12.General Diagnostic Table
A: INSPECTION
1. CLUTCH
Symptom Possible cause Corrective
1. Clutch slippage.
It is hard to perceive clutch slippage in
the early stage, but pay attention to the
following symptoms
 Engine speed up when shifting.
 High speed driving is impossible; espe-
cially rapid acceleration impossible and
vehicle speed does not increase in pro-
portion to an increase in engine speed.
 Power falls, particularly when ascend-
ing a slope, and there is a smell of burn-
ing of the clutch facing.
 Method of testing: Put the vehicle in
stationary condition with parking brake
fully applied. Disengage the clutch and
shift the transmission gear into the first.
Gradually allow the clutch to engage
while gradually increasing the engine
speed. The clutch function is satisfactory
if the engine stalls. However, the clutch is
slipping if the vehicle does not start off
and the engine does not stall.(a) Clutch facing smeared by oil Replace.
(b) Worn clutch facing Replace.
(c) Deteriorated diaphragm spring Replace.
(d) Distorted pressure plate or flywheel Replace.
(e) Defective release bearing holder Replace.
2. Clutch drags.
As a symptom of this trouble, a harsh
scratching noise develops and control
becomes quite difficult when shifting
gears. The symptom becomes more
apparent when shifting into the first gear.
However, because much trouble of this
sort is due to defective synchronization
mechanism, carry out the test as
described after.
 Method of testing: DIAGNOSTIC DIAGRAM OF CLUTCH
DRAG, INSPECTION, General Diagnos-
tic Table.>
It may be judged as insufficient disen-
gagement of clutch if any noise occurs
during this test.(a) Worn or rusty clutch disc hub spline Replace the clutch disc.
(b) Excessive deflection of clutch disc
facingReplace.
(c) Malfunction of crankshaft pilot bearing Replace.
(d) Cracked clutch disc facing Replace.
(e) Stuck clutch disc (smeared by oil or
water)Replace.
3. Clutch chatters.
Clutch chattering is an unpleasant vibra-
tion to the whole body when the vehicle is
just started with clutch partially engaged.(a) Adhesion of oil on the facing Replace the clutch disc.
(b) Weak or broken torsion spring Replace the clutch disc.
(c) Defective facing contact or excessive
disc wornReplace the clutch disc defection.
(d) Warped pressure plate or flywheel Replace.
(e) Loose disc rivets Replace the clutch disc.
(f) Loose engine mounting Retighten or replace the mounting.
(g) Improper adjustment of pitching stop-
perAdjustment.