light SUBARU FORESTER 2004 Service Repair Manual

EN(H4DOTC)-4
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)-5
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. ❏ Yes / ❏ 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:
 Had run out of gas before: ❏ 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)-7
ENGINE (DIAGNOSTIC)
General Description
12) Observe the following cautions when installing
a radio in MFI equipped models.
CAUTION:
 The antenna must be kept as far apart as pos-
sible from the control unit. (The ECM is located
under the steering column, inside of the instru-
ment panel lower trim panel.)
 The antenna feeder must be placed as far
apart as possible from the ECM and MFI har-
ness.
 Carefully adjust the antenna for correct
matching.
 When mounting a large power type radio, pay
special attention to the three items above men-
tioned.
 Incorrect installation of the radio may affect
the operation of the ECM.
13) Before disconnecting the fuel hose, disconnect
the fuel pump connector and crank the engine for
more than five seconds to release pressure in the
fuel system.If engine starts during this operation,
run it until it stops.
14) Problems in the electronic-controlled automatic
transmission may be caused by failure of the en-
gine, the electronic control system, the transmis-
sion proper, or by a combination of these.These
three causes (engine, electronic control system,
transmission) must be distinguished clearly when
performing diagnostics.
15) 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.
16) 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 1.2602) 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.
EN-00070

EN(H4DOTC)-9
ENGINE (DIAGNOSTIC)
Electrical Component Location
4. Electrical Component Location
A: LOCATION
1. ENGINE
 CONTROL MODULE
 LHD MODEL
 RHD MODEL
(1) Engine control module (ECM) (3) Data link connector (4) Test Mode Connector
(2) Malfunction indicator light
EN-00288(4)(2)(3)
(1)
EN-00289(1)
(2)(3)
(4)

EN(H4DOTC)-20
ENGINE (DIAGNOSTIC)
Electrical Component Location
2. TRANSMISSION
 UNIT
 LHD MODEL
 RHD MODEL
(1) Transmission Control Module
(TCM) (for AT model)(2) AT diagnostic indicator light (for AT
model)
EN-00325(1)(2)
EN-00326(1)
(2)

EN(H4DOTC)-21
ENGINE (DIAGNOSTIC)
Electrical Component Location
 SENSOR
(1) Rear vehicle speed sensor (AT
model)(3) Front vehicle speed sensor (AT
model)(5) ATF temperature sensor (AT
model)
(2) Front vehicle speed sensor (MT
model)(4) Torque converter turbine speed
sensor (AT model)(6) Brake light switch
(1)EN-00327(2)EN-00328
EN-00184 (3)
(1)EN-00107 (2)
EN-00186 (2)EN-00187(5)
EN-00188 (6)

EN(H4DOTC)-25
ENGINE (DIAGNOSTIC)
Engine Control Module (ECM) I/O Signal
Sensor power supply B136 16 5 5 —
Oil flow
control
solenoid
valve RHSignal (+) B134 18ON: 10 — 13
OFF: 0ON: 13 — 14
OFF: 0—
Signal (−) B134 28 0 0 —
Oil flow
control
solenoid
valve LHSignal (+) B134 19ON: 10 — 13
OFF: 0ON: 13 — 14
OFF: 0—
Signal (−) B134 29 0 0 —
Ignition
control#1 B135 18 0 13 — 14 Waveform
#2 B135 17 0 13 — 14 Waveform
#3 B135 16 0 13 — 14 Waveform
#4 B135 15 0 13 — 14 Waveform
Fuel injec-
tor#1 B136 6 10 — 13 1 — 14 Waveform
#2 B136 5 10 — 13 1 — 14 Waveform
#3 B136 4 10 — 13 1 — 14 Waveform
#4 B136 3 10 — 13 1 — 14 Waveform
Idle air
control
solenoid
valveSignal B134 27 0 or 13 — 14 0 or 13 — 14 Waveform
Fuel pump
control unitDiagnosis
signalB137 28 10 — 13 13 — 14 Waveform
Control
signalB135 27 0 or 5 0 or 5 —
A/C relay control B135 33ON: 0.5, or less
OFF: 10 — 13ON: 0.5, or less
OFF: 13 — 14—
Radiator fan relay 1 con-
trolB135 25ON: 0.5, or less
OFF: 10 — 13ON: 0.5, or less
OFF: 13 — 14—
Radiator fan relay 2 con-
trolB135 24ON: 0.5, or less
OFF: 10 — 13ON: 0.5, or less
OFF: 13 — 14Model with A/C
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
Fuel level sensor B136 20 0.12 — 4.75 0.12 — 4.75 —
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—
Wiper switch B137 23ON: 10 — 13
OFF: 0ON: 13 — 14
OFF: 0— DESCRIPTION Connector No. Terminal No.Signal (V)
NOTE
Ignition SW ON
(engine OFF)Engine ON
(Idling)

EN(H4DOTC)-31
ENGINE (DIAGNOSTIC)
OBD-II General Scan Tool
2. MODE $01 (CURRENT POWERTRAIN DIAGNOSTIC DATA)
Refers to data denoting the current operating condition of analog input/output, digital input/output and/or the
powertrain system.
A list of the support data and PID (Parameter Identification) codes are shown in the following table.
NOTE:
Refer to OBD-II general scan tool manufacturer’s instruction manual to access generic OBD-II PIDs (MODE
$01).
3. MODE $02 (POWERTRAIN FREEZE FRAME DATA)
Refers to data denoting the operating condition when trouble is sensed by the on-board diagnosis system.
A list of the support data and PID (Parameter Identification) codes are shown in the following table.
NOTE:
Refer to OBD-II general scan tool manufacturer’s instruction manual to access freeze frame data (MODE
$02).
PID Data Unit of measure
01Number of emission-related powertrain DTC and malfunction indicator light status Diagnosis
support dataON/OFF
03 Fuel system control status—
04 Calculated engine load value%
05 Engine coolant temperature°C
06 Short term fuel trim%
07 Long term whole fuel trim%
0B Intake manifold absolute pressure kPa, mmHg
0C Engine revolutionrpm
0D Vehicle speedkm/h
0E Ignition timing advance°
0F Intake air temperature°C
10 Air flow rate of manifold absolute pressure sensor g/sec
11 Throttle valve opening angle%
13 Check whether oxygen sensor is installed. —
15Oxygen sensor output voltage and short term fuel trim associated with oxygen sensor — bank
1V and %
1C On-board diagnostic system—
21 MI illuminating process—
24 A/F sensor 1 output voltage and short term fuel trim associated with A/F sensor 1 V and %
34 A/F sensor 1 current and lambda A and —
PID Data Unit of measure
02 DTC that caused CARB required freeze frame data storage —
03 Fuel system control status—
04 Calculated engine load value%
05 Engine coolant temperature°C
06 Short term fuel trim%
07 Long term whole fuel trim%
0B Intake manifold absolute pressure kPa, mmHg
0C Engine speedrpm
0D Vehicle speedkm/h
0E Ignition timing°
0F Intake air temperature°C
10 Amount of intake airg/s
11 Throttle opening%

EN(H4DOTC)-35
ENGINE (DIAGNOSTIC)
Subaru Select Monitor
NOTE:
For detailed operation procedure, refer to the “SUBARU SELECT MONITOR OPERATION MANUAL”.
5. READ CURRENT DATA FOR ENGINE (OBD MODE)
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 {Engine} and press the [YES] key.
3) Press the [YES] key after the information of engine type was displayed.
4) On the «Engine Diagnosis» display screen, select the {OBD System} and press the [YES] key.
5) On the «OBD Menu» screen, select the {Current Data Display/Save}, and then press the [YES] key.
6) On the «Data Display Menu» screen, select the {Data Display} and press the [YES] key.
7) Using the scroll key, move the display screen up or down until the desired data is shown.
 A list of the support data is shown in the following table.
Air conditioning signal A/C Compressor Signal ON or OFF
Radiator main fan relay signal Radiator Fan Relay #1 ON or OFF
Knocking signal Knocking Signal ON or OFF
Radiator sub fan relay signal Radiator Fan Relay #2 ON or OFF
Power steering switch signal P/S Switch ON or OFF
Engine torque control permission signal Torque Permission Signal ON or OFF
Rear oxygen sensor rich signal Rear Oxygen Rich Signal ON or OFF
Starter switch signal Starter Switch ON or OFF
Idle switch signal Idle Switch ON or OFF
Crankshaft position sensor signal Crankshaft Position Sig. ON or OFF
Camshaft position sensor signal Camshaft Position Sig. ON or OFF
Rear defogger switch signal Rear Defogger SW ON or OFF
Blower fan switch signal Blower Fan SW ON or OFF
Small light switch signal Light Switch ON or OFF
Tumble generated valve output signal TGV Output ON or OFF
Exhaust temperature signal Exhaust Gas Temperature°C
Estimated cumulative driving distance Odd Meter km
Roughness Monitor for #1 cylinder Roughness Monitor #1 —
Roughness Monitor for #2 cylinder Roughness Monitor #2 —
Roughness Monitor for #3 cylinder Roughness Monitor #3 —
Roughness Monitor for #4 cylinder Roughness Monitor #4 —
Wiper switch signal Wiper Switch ON or OFF
A/C middle pressure switch signal A/C Mid pressure switch ON or OFF
AT retard angle demand signal Retard Signal from AT ON or OFF
AT fuel cut demand signal Fuel Cut Signal from AT ON or OFF
Description Display Unit of measure
Number of diagnosis code Number of Diag. Code —
Condition of malfunction indicator light MI (MIL) ON or OFF
Monitoring test of misfire Misfire monitoring Complete or incomplete
Monitoring test of fuel system Fuel system monitoring Complete or incomplete
Monitoring test of comprehensive component Component monitoring Complete or incomplete
Test of catalyst Catalyst Diagnosis Complete or incomplete
Test of heating-type catalyst Heated catalyst No support
Test of evaporative emission purge control system Evaporative purge system No support
Test of secondary air system Secondary air system No support
Test of air conditioning system refrigerant A/C system refrigerant No support
Test of oxygen sensor Oxygen sensor Complete or incomplete
Test of oxygen sensor heater Oxygen Heater Diagnosis Complete or incomplete
Test of EGR system EGR system No supportRemarks Display Unit of measure

EN(H4DOTC)-36
ENGINE (DIAGNOSTIC)
Subaru Select Monitor
NOTE:
For detailed operation procedure, refer to the “SUBARU SELECT MONITOR OPERATION MANUAL”.
6. READ FREEZE FRAME DATA FOR ENGINE. (OBD MODE)
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 {Engine} and press the [YES] key.
3) Press the [YES] key after the information of engine type was displayed.
4) On the «Engine Diagnosis» display screen, select the {OBD System} and press the [YES] key.
5) On the «OBD Menu» display screen, select the {Freeze Frame Data} and press the [YES] key.
 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”.
Air fuel ratio control system for bank 1 Fuel System for Bank 1 —
Engine load data Calculated load value %
Engine coolant temperature signal Coolant Temp.°C or °F
Short term fuel trim by front oxygen (A/F) sensor Short term fuel trim B1 %
Long term fuel trim by front oxygen (A/F) sensor Long term fuel trim B1 %
Intake manifold absolute pressure signal Mani. Absolute Pressure mmHg, kPa, inHg or psi
Engine speed signal Engine Speed rpm
Vehicle speed signal Vehicle Speed km/h or MPH
Ignition timing advance for #1 cylinder Ignition timing adv. #1°
Intake air temperature signal Intake Air Temp.°C or °F
Amount of intake air Mass Air Flow g/s
Throttle position signal Throttle Opening Angle %
Rear oxygen sensor output signal Oxygen Sensor #12 V
Air fuel ratio correction by rear oxygen sensor Short term fuel trim #12 %
On-board diagnostic system OBD System —
Rear oxygen sensor signal Oxygen Sensor #11 —
Rear oxygen sensor signal Oxygen Sensor #12 —
Malfunction indicator light illuminating process Lighted MI Lamp History —
A/F sensor output signal (voltage) A/F sensor #11 V
A/F lambda signal A/F sensor #11 —
A/F sensor lambda signal A/F sensor #11 —
A/F sensor signal (power supply) A/F sensor #11 mA
Description Display Unit of measure
Diagnostic code of freeze frame data Freeze frame data Diagnostic code
Air fuel ratio control system for bank 1 Fuel system for Bank 1 —
Air fuel ratio control system for bank 2 Fuel System for Bank 2 —
Engine load data Calculated Load Valve %
Engine coolant temperature signal Coolant Temp.°C or °F
Short term fuel trim by front oxygen (A/F) sensor Short term fuel trim B1 %
Long term fuel trim by front oxygen (A/F) sensor Long term fuel trim B1 %
Intake manifold absolute pressure signal Mani. Absolute Pressure mmHg, kPa, inHg or psi
Engine speed signal Engine Speed rpm
Vehicle speed signal Vehicle Speed km/h or MPH
Ignition timing advance for #1 cylinder Ignition timing adv. #1°
Intake air temperature signal Intake Air Temp.°C or °F
Amount of intake air Mass Air Flow g/s
Throttle position signal Throttle Opening Angle %Description Display Unit of measure