2004 SUBARU FORESTER engine coolant

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)-8
ENGINE (DIAGNOSTIC)
General Description
 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.
2. ENGINE AND EMISSION CONTROL SYS-
TEM
 MFI system is a system that supplies the opti-
mum air-fuel mixture to the engine for all the vari-
ous operating conditions through the use of the
latest electronic technology.
With this system fuel, which is pressurized at a con-
stant pressure, is injected into the intake air pas-
sage of the cylinder head.The injection quantity of
fuel is controlled by an intermittent injection system
where the electro-magnetic injection valve (fuel in-
jector) opens only for a short period of time, de-
pending on the quantity of air required for one cycleof operation.In actual operation, the injection quan-
tity is determined by the duration of an electric sig-
nal applied to the fuel injector and this permits
simple, yet highly precise metering of the fuel.
 Further, all the operating conditions of the engine
are converted into electric signals, and this results
in additional features of the system, such as large
improved adaptability, easier addition of compen-
sating element, etc.
The MFI system also has the following features:
 Reduced emission of harmful exhaust gases.
 Reduced in fuel consumption.
 Increased engine output.
 Superior acceleration and deceleration.
 Excellent engine start and 3warm-up perfor-
mance by the correction of engine coolant tem-
perature and intake air temperature.
D: PREPARATION 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)
ST24082AA230
ST22771AA030

EN(H4DOTC)-11
ENGINE (DIAGNOSTIC)
Electrical Component Location
 SENSOR
(1) Manifold absolute pressure sensor (4) Knock sensor (7) Mass air flow and intake air tem-
perature sensor
(2) Engine coolant temperature sen-
sor(5) Camshaft position sensor
(6) Crankshaft position sensor (8) Tumble generator valve position
sensor (3) Throttle position sensor
EN-00293
(1)
(7) (6) (4) (8) (5)(2)
(3)

EN(H4DOTC)-23
ENGINE (DIAGNOSTIC)
Engine Control Module (ECM) I/O Signal
5. Engine Control Module (ECM) I/O Signal
A: ELECTRICAL SPECIFICATION
DESCRIPTION Connector No. Terminal No.Signal (V)
NOTE
Ignition SW ON
(engine OFF)Engine ON
(Idling)
Crank-
shaft posi-
tion sensorSignal (+) B135 10 0−7 — +7 Waveform
Signal (−) B135 22 0 0 —
Shield B135 31 0 0 —
Camshaft
position
sensorSignal (+) B135 11 0−7 — +7 Waveform
Signal (−) B135 23 0 0 —
Shield B135 31 0 0 —
Throttle
position
sensorSignal B136 18Fully closed: 0.2 — 1.0
Fully opened: 4.2 — 4.7—
Pow er
supplyB136 16 5 5 —
GND
(sensors)B136 35 0 0 —
Rear Oxy-
gen Sen-
sorSignal B137 25 0 0 — 0.9 —
Shield B137 31 0 0 —
GND
(sensors)B136 35 0 0 —
Fr o nt ox y-
gen (A/F)
sensor
heaterSignal 1 B134 3 0 — 1.0 0 — 1.0 Waveform
Signal 2 B134 2 0 — 1.0 0 — 1.0 Waveform
Rear oxygen sensor
heater signalB135 2 0 — 1.0 0 — 1.0 Waveform
Engine
coolant
tempera-
ture sen-
sorSignal B136 14 1.0 — 1.4 1.0 — 1.4 After engine is warmed-up.
GND
(sensors)B136 35 0 0 After engine is warmed-up.
Vehicle speed signal B135 26 0 or 5 0 or 5“5” and “0” are repeatedly dis-
played when vehicle is driven.
EN-02308
B134
34
3330 31 3229 26
27
28 25
1
2
8 9 310
11 12
19 20 21 13 14
15
16 17
18 22 23 24
3330 31 32
29 26
27
28 25
7
8 9 5 64
10
11 12
19 20 21 13 14
15 16
17
18 22
23 241
2 3
7 5 64
3534
B137 B135
B136
33
30 31
32
29 26
27
28 25
8 910
11 12
19
20 21 13 14
15 16 17
18
22
23 241
2
3
75 64
3534
30 3129
26
27
28 25
8 910
11 12
19 20 21 13 14
15 16 17
18 22
23 241 2
3
75 64

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)-34
ENGINE (DIAGNOSTIC)
Subaru Select Monitor
4. READ CURRENT DATA FOR ENGINE. (NORMAL 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» screen, select the {Current Data Display/Save}, and then press the [YES] key.
5) On the «Data Display Menu» screen, select the {Data Display} and press the [YES] key.
6) 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.
Remarks Display Unit of measure
Battery voltage Battery Voltage V
Vehicle speed signal Vehicle Speed km/h or MPH
Engine speed signal Engine Speed rpm
Engine coolant temperature signal Coolant Temp.°C or °F
Ignition timing signal Ignition Timing deg
Throttle position signal Throttle Opening Angle %
Throttle position signal Throttle Sensor Voltage V
Injection pulse width Fuel Injection #1 Pulse ms
Idle air control signal ISC Valve Duty Ratio %
generated duty control signal ALT Duty %
Fuel pump duty control signal Fuel Pump Duty %
A/F sensor current A/F Sensor #1 Current mA
A/F sensor resistance A/F Sensor #1 ResistanceΩ
Front oxygen (A/F) sensor output signal A/F Sensor #1 —
Rear oxygen sensor output signalRear O
2 Sensor
V
Short term fuel trim A/F Correction #1 %
Knock sensor correction Knocking Correction deg
Atmospheric pressure signal Atmosphere Pressure mmHg, kPa, inHg or psi
Intake manifold relative pressure signal Mani. Relative Pressure mmHg, kPa, inHg or psi
Intake manifold absolute pressure signal Mani. Absolute Pressure mmHg, kPa, inHg or psi
A/F correction (short term fuel trim) by rear oxygen sensor A/F Correction #3 %
Long term whole fuel trim A/F Learning #1 %
Canister purge control solenoid valve duty ratio CPC Valve Duty Ratio %
Primary supercharged pressure control signal Primary Control %
Tumble generated valve position sensor signal (RH side) TGV Position Sensor R V
Tumble generated valve position sensor signal (LH side) TGV Position Sensor L V
Tumble generated valve drive signal TGV Drive OPEN or CLOSE
Fuel level signal Fuel Level Voltage V
Intake air temperature signal Intake Air Temp.°C or °F
Mass air flow sensor signal Mass Air Flow g/s
Mass air flow sensor signal Air Flow Sensor Voltage V
Valve Timing Signal VVT Adv. Ang. amount R deg
Valve Timing Signal VVT Adv. Ang. amount L deg
Oil flow control solenoid valve signal OCV Duty R %
Oil flow control solenoid valve signal OCV Duty L %
Oil flow control solenoid valve current OCV current R mA
Oil flow control solenoid valve current OCV Current L mA
AT/MT identification signal AT Vehicle ID Signal AT or MT
Test Mode Signal Test Mode Signal ON or OFF
Load switch signal Electric Load Signal ON or OFF
Ignition switch signal Ignition Switch ON or OFF
Neutral position switch signal Neutral Position Switch ON or OFF
Air conditioning switch signal A/C Switch ON or OFF

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

EN(H4DOTC)-40
ENGINE (DIAGNOSTIC)
Inspection Mode
12.Inspection Mode
A: OPERATION
Perform the diagnosis on the “Diagnosis Trouble Codes (DTC) List” below.
Refer to the item of drive cycle when perform the diagnosis not on the “Diagnosis Trouble Codes (DTC) List”
below.
DTC Item On condition
P0011 A Camshaft Position-Timing Over-Advanced or System Performance (Bank 1) —
P0021 A Camshaft Position-Timing Over-Advanced or System Performance (Bank 2) —
P0031 HO2S Sensor Circuit Low Voltage (Bank 1 Sensor 1) —
P0032 HO2S Sensor Circuit High Voltage (Bank 1 Sensor 1) —
P0037 HO2S Sensor Circuit Low Voltage (Bank 1 Sensor 2) —
P0038 HO2S Sensor Circuit High Voltage (Bank 1 Sensor 2) —
P0102 Mass or Volume Air Flow Circuit Low Input —
P0103 Mass or Volume Air Flow Circuit High Input —
P0107 Manifold Absolute Pressure/Barometric Pressure Circuit Low Input —
P0108 Manifold Absolute Pressure/Barometric Pressure Circuit High Input —
P0112 Intake Air Temperature Circuit Low Input —
P0113 Manifold Absolute Pressure/Barometric Pressure Circuit High Input —
P0117 Engine Coolant Temperature Circuit Low Input —
P0118 Engine Coolant Temperature Circuit High Input —
P0122 Throttle/Pedal Position Sensor/Switch “A” Circuit Low Input —
P0123 Throttle/Pedal Position Sensor/Switch “A” Circuit High Input —
P0129 Barometric Pressure Too Low —
P0130 O
2 Sensor Circuit (Bank 1 Sensor 1) —
P0131 O
2 Sensor Circuit Low Voltage (Bank 1 Sensor 1) —
P0132 O
2 Sensor Circuit High Voltage (Bank 1 Sensor 1) —
P0134 O
2 Sensor Circuit No Activity Detected (Bank 1 Sensor 1) —
P0137 O
2 Sensor Circuit Low Voltage (Bank 1 Sensor 2) —
P0138 O
2 Sensor Circuit High Voltage (Bank 1 Sensor 2) —
P0171 System Too Lean (Bank 1) —
P0172 System Too Rich (Bank 1) —
P0230 Fuel Pump Primary Circuit —
P0245 Turbo/Super Charger Wastegate Solenoid “A” Low —
P0327 Knock Sensor 1 Circuit Low Input (Bank 1 or Single Sensor) —
P0328 Knock Sensor 1 Circuit High Input (Bank 1 or Single Sensor) —
P0335 Crankshaft Position Sensor “A” Circuit —
P0336 Crankshaft Position Sensor “A” Circuit Range/Performance —
P0340 Camshaft Position Sensor “A” Circuit (Bank 1 or Single Sensor) —
P0341Camshaft Position Sensor “A” Circuit Range/Performance (Bank 1 or Single
Sensor)—
P0365 Camshaft Position Sensor “B” Circuit (Bank 1) —
P0390 Camshaft Position Sensor “B” Circuit (Bank 2) —
P0458 Evaporative Emission Control System Purge Control Valve Circuit Low —
P0462 Fuel Level Sensor Circuit Low Input —
P0463 Fuel Level Sensor Circuit High Input —
P0502 Vehicle Speed Sensor Circuit Low Input —
P0503 Vehicle Speed Sensor Intermittent/Erratic/High —
P0509 Idle Control System Circuit High —
P0512 Starter Request Circuit—
P0513 Incorrect Immobilizer Key —
P0519 Idle Control System Malfunction (Fail-Safe) —