2004 SUBARU FORESTER light

EN(H4DOTC)-261
ENGINE (DIAGNOSTIC)
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
Step Check Yes No
1 CHECK CURRENT DATA.
1) Start the engine.
2) Read the data of tumble generator valve
position sensor signal using Subaru Select
Monitor or OBD-II general scan tool.
N
OTE:
 Subaru Select Monitor
For detailed operation procedure, refer to
“READ CURRENT DATA SHOWN ON DIS-
PLAY FOR ENGINE”. 33, Subaru Select Monitor.>
 OBD-II general scan tool
For detailed operation procedures, refer to the
OBD-II General Scan Tool Operation Manual.Is the voltage more than 4.9 V? Go to step 2.Even if the mal-
function indicator
light illuminates,
the circuit has
returned to a nor-
mal condition at
this time.A tempo-
rary poor contact
of the connector
may be the cause.
N
OTE:
In this case repair
the following:
 Poor contact in
tumble generator
valve position sen-
sor connector
 Poor contact in
ECM connector.
 Poor contact in
coupling connector
2 CHECK HARNESS BETWEEN TUMBLE
GENERATOR VALVE POSITION SENSOR
AND ECM CONNECTOR.
1) Turn the ignition switch to OFF.
2) Disconnect the connectors from throttle
position sensor.
3) Measure the resistance of harness
between tumble generator valve position sen-
sor connector and engine ground.
Connector & terminal
(E54) No. 2 — Engine ground:Is the resistance less than 5
Ω?Go to step 3.Repair the har-
ness and connec-
tor.
N
OTE:
In this case repair
the following:
 Open circuit in
harness between
tumble generator
valve position sen-
sor and ECM con-
nector
 Poor contact in
coupling connector
 Poor contact in
joint connector
3 CHECK HARNESS BETWEEN TUMBLE
GENERATOR VALVE POSITION SENSOR
AND ECM CONNECTOR.
1) Turn the ignition switch to ON.
2) Measure the voltage between throttle posi-
tion sensor connector and engine ground.
Connector & terminal
(E54) No. 3 (+) — Engine ground (
−):Is the voltage more than 4.9 V? Repair battery
short circuit in har-
ness between tum-
ble generator valve
position sensor
and ECM connec-
tor.After repair,
replace the ECM.
FU(H4DOTC)-50,
Engine Control
Module (ECM).>Replace the tum-
ble generator valve
assembly. FU(H4DOTC)-42,
Tu m b l e G e n e r a t o r
Valve Assembly.>

ENGINE (DIAGNOSTIC)
EN(H4DOTC 2.5)
Page
1. Basic Diagnostics Procedure ......................................................................2
2. Check List for Interview ...............................................................................3
3. General Description ....................................................................................5
4. Electrical Component Location ...................................................................8
5. Engine Control Module (ECM) I/O Signal .................................................17
6. Engine Condition Data ..............................................................................22
7. Data Link Connector .................................................................................23
8. OBD-II General Scan Tool ........................................................................24
9. Subaru Select Monitor...............................................................................27
10. Read Diagnostic Trouble Code (DTC) ......................................................34
11. Inspection Mode ........................................................................................35
12. Drive Cycle ................................................................................................40
13. Clear Memory Mode..................................................................................42
14. Compulsory Valve Operation Check Mode ...............................................43
15. Malfunction Indicator Light ........................................................................45
16. Diagnostics for Engine Starting Failure .....................................................54
17. List of Diagnostic Trouble Code (DTC) .....................................................65
18. Diagnostic Procedure with Diagnostic Trouble Code (DTC) .....................70
19. General Diagnostic Table........................................................................258

EN(H4DOTC 2.5)-2
ENGINE (DIAGNOSTIC)
Basic Diagnostics Procedure
1. Basic Diagnostics Procedure
A: PROCEDURE
1. ENGINE
Step Check Yes No
1 CHECK ENGINE START FAILURE.
1) Ask the customer when and how the trou-
ble occurred using the interview check list.
Check List for Interview.>
2) Start the engine.Does the engine start? Go to step 2.Inspection using
“Diagnostics for
Engine Start Fail-
ure”. EN(H4DOTC 2.5)-
54, Diagnostics for
Engine Starting
Fai lu r e.>
2 CHECK ILLUMINATION OF MALFUNCTION
INDICATOR LIGHT.Does malfunction indicator
light illuminate?Go to step 3.Inspection using
“General Diagnos-
tic Table”. EN(H4DOTC 2.5)-
258, General Diag-
nostic Table.>
3 CHECK INDICATION OF DTC ON DISPLAY.
1) Turn the ignition switch to OFF.
2) Connect the Subaru Select Monitor or the
OBD-II general scan tool to data link connec-
tor.
3) Turn the ignition switch to ON and the Sub-
aru Select Monitor or OBD-II general scan tool
switch to ON.
4) Read the DTC on the Subaru Select Moni-
tor or OBD-II general scan tool.Does the Subaru Select Moni-
tor or OBD-II general scan tool
indicate DTC?Record the DTC.
Repair the trouble
cause. EN(H4DOTC 2.5)-
65, List of Diag-
nostic Trouble
Code (DTC).> Go
to step 4.Repair the related
parts.
N
OTE:
If DTC is not shown
on display although
the malfunction in-
dicator light illumi-
nates, perform the
diagnostics for mal-
function indicator
light circuit or com-
bination meter.
EN(H4DOTC 2.5)-
45, Malfunction In-
dicator Light.>
4 PERFORM THE DIAGNOSIS.
1) Perform clear memory mode. EN(H4DOTC 2.5)-42, Clear Memory Mode.>
2) Perform the “INSPECTION MODE”. to EN(H4DOTC 2.5)-35, Inspection Mode.>Does the Subaru Select Moni-
tor or OBD-II general scan tool
indicate DTC?Check on “Diag-
nostic Chart with
Diagnostic Trou-
ble Code (DTC)”.
EN(H4DOTC 2.5)-
70, Diagnostic
Procedure with
Diagnostic Trou-
ble Code (DTC).>Finish the diagno-
sis.

EN(H4DOTC 2.5)-3
ENGINE (DIAGNOSTIC)
Check List for Interview
2. Check List for Interview
A: INSPECTION
1. CHECK LIST No. 1
Check the following items when problem has occurred.
NOTE:
Use copies of this page for interviewing customers.
Customer’s name Engine No.
Date of sale Fuel brand
Date of repair
Odometer readingkm
V.I.N.miles
Weather❏ Fine
❏ Cloudy
❏ Rainy
❏ Snowy
❏ Va r i o u s / O t h e r s :
Ambient air temperature°C (°F)
❏ Hot
❏ War m
❏ Cool
❏ Cold
Place❏ Highway
❏ Suburbs
❏ Inner city
❏ Uphill
❏ Downhill
❏ Rough road
❏ Others:
Engine temperature❏ Cold
❏ War ming-up
❏ After warming-up
❏ Any temperature
❏ Others:
Engine speed rpm
Vehicle speed km/h (MPH)
Driving conditions❏ Not affected
❏ At starting
❏ While idling
❏ At racing
❏ While accelerating
❏ While cruising
❏ While decelerating
❏ While turning (RH/LH)
Headlight❏ ON / ❏ OFF Rear defogger❏ ON / ❏ OFF
Blower❏ ON / ❏ OFF Radio❏ ON / ❏ OFF
A/C compressor❏ ON / ❏ OFF CD/Cassette❏ ON / ❏ OFF
Radiator fan❏ ON / ❏ OFF Car phone❏ ON / ❏ OFF
Fr o nt wi pe r❏ ON / ❏ OFF CB❏ ON / ❏ OFF
Rear Wiper❏ ON / ❏ OFF

EN(H4DOTC 2.5)-4
ENGINE (DIAGNOSTIC)
Check List for Interview
2. CHECK LIST No. 2
Check the following items about the vehicle’s state when malfunction indicator light turns on.
NOTE:
Use copies of this page for interviewing customers.
a) Other warning lights or indicators turn on. ❏ Ye s / ❏ No
❏ Low fuel warning light
❏ Charge indicator light
❏ AT diagnostic indicator light
❏ ABS Warning Light
❏ Oil pressure indicator light
b) Fuel level
 Lack of gasoline: ❏ Yes / ❏ No
 Indicator position of fuel gauge:
 Experienced running out of fuel: ❏ Ye s / ❏ No
c) Intentional connecting or disconnecting of harness connectors or spark plug cords: ❏ Yes / ❏ No
 What:
d) Intentional connecting or disconnecting of hoses: ❏ Ye s / ❏ No
 What:
e) Installing of other parts except genuine parts: ❏ Ye s / ❏ No
 What:
 Where:
f) Occurrence of noise: ❏ Yes / ❏ No
From where:
 What kind:
g) Occurrence of smell: ❏ Yes / ❏ No
From where:
 What kind:
h) Intrusion of water into engine compartment or passenger compartment: ❏ Yes / ❏ No
i) Troubles occurred
❏ Engine does not start
❏ Engine stalls during idling
❏ Engine stalls while driving
❏ Engine speed decreases
❏ Engine speed does not decrease
❏ Rough idling
❏ Poor acceleration
❏ Back fire
❏ After fire
❏ Does not shift
❏ Excessive shift shock

EN(H4DOTC 2.5)-6
ENGINE (DIAGNOSTIC)
General Description
13) Diagnostics should be conducted by rotating
with simple, easy operations and proceeding to
complicated, difficult operations. The most impor-
tant thing in diagnostics is to understand the cus-
tomer’s complaint, and distinguish between the
three causes.
14) On the model with ABS, when performing driv-
ing test in jacked-up or lifted-up position, some-
times the warning light may be lit, but this is not a
malfunction of the system. The reason for this is the
speed difference between the front and rear
wheels. After diagnosis of engine control system,
perform the ABS memory clearance procedure of
self-diagnosis function.
B: INSPECTION
Before performing diagnostics, check the following
items which might affect engine problems:
1. BATTERY
1) Measure battery voltage and specific gravity of
electrolyte.
Standard voltage: 12 V
Specific gravity: Above 1.260
2) Check the condition of the main and other fuses,
and harnesses and connectors. Also check for
proper grounding.
2. ENGINE GROUND
Make sure the engine ground terminal is properly
connected to the engine.
C: NOTE
1. GENERAL DESCRIPTION
 On-board diagnosis (OBD) system detects and
indicates a fault in various inputs and outputs of the
complex electronic control. Malfunction indicator
light in the combination meter indicates occurrence
of a fault or trouble.
 Further, against such a failure or sensors as may
disable the drive, the fail-safe function is provided
to ensure the minimal driveability.
 The OBD system incorporated with the vehicles
within this engine family complies with Section
1968.1, California Code of Regulations (OBD-II
regulation). The OBD system monitors the compo-
nents and the system malfunction listed in Engine
Section which affects on emissions.
 When the system decides that a malfunction oc-
curs, malfunction indicator light illuminates. At the
same time of the malfunction indicator light illumi-
nation or blinking, the DTC and a freeze frame en-
gine conditions are stored into on-board computer.
 The OBD system stores freeze frame engine
condition data (engine load, engine coolant tem-
perature, fuel trim, engine speed and vehicle
speed, etc.) into on-board computer when it detects
a malfunction first.
 If the OBD system detects the various malfunc-
tions including the fault of fuel trim or misfire, the
OBD system first stores freeze frame engine condi-
tions about the fuel trim or misfire.
 When the malfunction does not occur again for
three consecutive driving cycles, malfunction indi-
cator light is turned off, but DTC remains at on-
board computer.
 The OBD-II system is capable of communication
with a general scan tool (OBD-II general scan tool)
formed by ISO 9141 CARB.
 The OBD-II diagnostics procedure is different
from the usual diagnosis procedure. When trouble-
shooting the OBD-II models, connect Subaru Se-
lect Monitor or the OBD-II general scan tool to the
vehicle.
EN-01201

EN(H4DOTC 2.5)-8
ENGINE (DIAGNOSTIC)
Electrical Component Location
4. Electrical Component Location
A: LOCATION
1. ENGINE
 CONTROL MODULE
(1) Engine control module (ECM) (3) Test Mode Connector (5) Data link connector
(2) Malfunction indicator light (4) Diagnosis connector
EN-00072
(3) (2)
(4) (1)(5)
EN-00235
(1)
(2)EN-00004
PI-00014
(4)
(3)
AT-00326 (5)

EN(H4DOTC 2.5)-19
ENGINE (DIAGNOSTIC)
Engine Control Module (ECM) I/O Signal
Radiator fan relay 2 con-
trolB135 24ON: 0.5, or less
OFF: 10 — 13ON: 0.5, or less
OFF: 13 — 14Model with A/C only
Malfunction indicator
lightB134 17 — —Light “ON”: 1, or less
Light “OFF”: 10 — 14
Engine speed output B134 23 — 0 — 13, or more Waveform
Purge control solenoid
valveB134 14ON: 1, or less
OFF: 10 — 13ON: 1, or less
OFF: 13 — 14Wavefor m
Manifold
absolute
pressure
sensorSignal B136 22 1.7 — 2.4 1.1 — 1.6
— Pow er
supplyB136 16 5 5
GND
(sensors)B136 35 0 0
Small light switch B137 12ON: 0
OFF: 10 — 13ON: 0
OFF: 13 — 14—
Blower fan switch B137 13ON: 0
OFF: 10 — 13ON: 0
OFF: 13 — 14—
Rear defogger switch B137 11ON: 0
OFF: 10 — 13ON: 0
OFF: 13 — 14—
Power steering oil pres-
sure switchB137 10 10 — 13ON: 0
OFF: 13 — 14—
Front oxygen (A/F) sen-
sor signal (+)B134 33 2.8 — 3.2 2.8 — 3.2 —
Front oxygen (A/F) sen-
sor signal (−)B134 26 2.4 — 2.7 2.4 — 2.7 —
Front oxygen (A/F) sen-
sor shieldB134 25 0 0 —
SSM/GST communica-
tion lineB137 20 1 ← → 41 ← → 4—
GND (injector) B137 7 0 0 —
GND (ignition system) B135 12 0 0 —
GND (power supply)B135 4 0 0 —
B135 1 0 0 —
GND (control system)B137 1 0 0 —
B137 2 0 0 —
GND (Front oxygen (A/F)
sensor heater 1)B134 7 0 0 —
GND (Front oxygen (A/F)
sensor heater 2)B134 6 0 0 —
Camshaft position sen-
sor (LH)B135 8 0 — 0.9ON: 0
OFF: 4.7 — 5.3Wavefor m
Camshaft position sen-
sor (RH)B135 9 0 — 0.9ON: 0
OFF: 4.7 — 5.3Wavefor m
Fuel level sensor B136 20 0.12 — 4.75 0.12 — 4.75 —
Electronic
throttle
controlMain B136 180.64 — 0.72
Fully opens:
3.960.64 — 0.72
(After engine is
warmed-up.)Fully closed: 0.6 Fully opens:
3.96
Sub B136 291.51 — 1.58
Fully opens:
4.171.51 — 1.58
(After engine is
warmed-up)Fully closed: 1.48 Fully opens:
4.17
Pow er
supplyB136 16 5 5 —
GND
(sensor)B137 3 0 0 — DESCRIPTION Connector No. Terminal No.Signal (V)
NOTE
Ignition SW ON
(engine OFF)Engine ON
(Idling)