EN(H6DO)(diag)-6
General Description
ENGINE (DIAGNOSTICS)
C: NOTE
1. GENERAL DESCRIPTION
•The on-board diagnostics (OBD) system detects
and indicates a fault in various inputs and outputs
of the complex electronic control. Malfunction indi-
cator light in the combination meter indicates oc-
currence 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 drivability.
•The OBD system incorporated with the vehicles
within this engine family complies with OBD-II Reg-
ulations. 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, a 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 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.
•When troubleshooting the vehicle which com-
plies with OBD-II Regulations, connect the Subaru
Select Monitor or general scan tool to the vehicle.
2. ENGINE AND EMISSION CONTROL SYS-
TEM
•The Multipoint Fuel Injection (MFI) system is a
system that supplies the optimum air-fuel mixture
to the engine for all the various operating condi-
tions through the use of the latest electronic tech-
nology.
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 cycle
of operation. In actual operation, the injection quan-
tity is determined by the duration of an electric
pulse 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.
•Superior startability and warm-up perfor-
mance in cold weather since compensation is
made for coolant and intake air temperature.
EN(H6DO)(diag)-9
Electrical Component Location
ENGINE (DIAGNOSTICS)
•Sensor
(1) Mass air flow and intake air tem-
perature sensor
(3) Engine coolant temperature sen-
sor
(6) Camshaft position sensor
(7) Crankshaft position sensor
(2) Manifold absolute pressure sensor (4) Electronic throttle control (8) Oil temperature sensor
(5) Knock sensor
EN-03684
(6)(6) (8)
(3)(2)
(7)
(1)
(4) (5)(5)
EN(H6DO)(diag)-16
Engine Control Module (ECM) I/O Signal
ENGINE (DIAGNOSTICS)
5. Engine Control Module (ECM) I/O Signal
A: ELECTRICAL SPECIFICATION
DescriptionConnector
No.
Te r m i n a l
No.
Signal (V)
ReferenceIgnition SW ON
(engine OFF)
Engine ON
(idling)
Crankshaft Position
Sensor
Signal (+) B134 13 0 –7 — +7 Waveform
Signal (–) B134 14 0 0 —
Shield B134 24 0 0 —
Camshaft position sensor (LH) B134 11 0.275 0 or 5 Waveform
Camshaft position sensor (RH) B134 21 0.275 0 or 5 Waveform
Camshaft position sensor
(ground)B134 22 0 0 —
Electronic throttle
control
Main B134 180.64 — 0.94
Fully opened: 4.01
0.64 — 0.72
(After engine is
warmed-up.)
Fully closed: 0.6
Fully opened: 4.01
Sub B134 281.51 — 1.76
Fully opened: 4.23
1.51 — 1.58
(After engine is
warmed-up.)
Fully closed: 1.48
Fully opened: 4.23
Electronic throttle control motor
(+)B137 5 Duty waveform Duty waveformDrive frequency: 500
Hz
Electronic throttle control motor (–) B137 4 Duty waveform Duty waveformDrive frequency: 500
Hz
Electronic throttle control motor
power supplyB136 1 10 — 13 12 — 14 —
Electronic throttle control motor
relayB136 21ON: 0
OFF: 10 — 13
ON: 0
OFF: 13 — 14
When ignition switch
is turned to ON: ON
Accelerator pedal
position sensor
Main B135 23Fully closed: 0.7
Fully opened: 3.5
Fully closed: 0.7
Fully opened: 3.5—
Powe r s up -
ply (main)B135 21 5 5 —
Ground
(main)B135 29 0 0 —
Sub B135 31Fully closed: 0.7
Fully opened: 3.5
Fully closed: 0.7
Fully opened: 3.5—
Engine coolant temperature sen-
sorB134 34 1.0 — 1.4 1.0 — 1.4After engine is
warmed-up.
EN-01812
B134
5678219431024 2223251112131415262728
1617181920213334 2932 3031
B136
5678219431024 2223251112131415262728
16171819202133342932303135
B135
5678219431024 2223251112131415262728
16171819202129303132333435
B137
5678219431022231112131415242526
1617181920212728293031
ToToToTo
EN(H6DO)(diag)-23
General Scan Tool
ENGINE (DIAGNOSTICS)
2. MODE $01 (CURRENT POWERTRAIN DIAGNOSTIC DATA)
Refer to data denoting the current operating condition of analog input/output, digital input/output or the pow-
ertrain system.
A list of the support data and PID (Parameter Identification) codes are shown in the following table.
NOTE:
Refer to general scan tool manufacturer’s operation manual to access generic OBD-II PIDs (MODE $01).
PID Data Unit of measure
01 Number of emission-related powertrain DTC and malfunction indicator light status ON/OFF
03 Fuel system control status—
04 Calculated engine load value%
05 Engine coolant temperature°C
06 Short term fuel trim (Bank 1)%
07 Long term fuel trim (Bank 1)%
08 Short term fuel trim (Bank 2)%
09 Long term fuel trim (Bank 2)%
0B Intake manifold absolute pressure kPa
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. —
15 Oxygen sensor output voltage (Bank 1 Sensor 2) V
15 Oxygen sensor compensation (Bank 1 Sensor 2) %
19 Oxygen sensor output voltage (Bank 2 Sensor 2) V
1C On-board diagnostic system—
24 Oxygen sensor output voltage and short term fuel trim associated with oxygen sensor (bank 1) V and %
28 Oxygen sensor output voltage and short term fuel trim associated with oxygen sensor (bank 2) V and %
34 A/F sensor lambda value (Bank 1 Sensor 1) —
34 A/F sensor current value (Bank 1 Sensor 1) mA
38 A/F sensor lambda value (Bank 2 Sensor 1) —
38 A/F sensor current value (Bank 2 Sensor 1) mA
EN(H6DO)(diag)-24
General Scan Tool
ENGINE (DIAGNOSTICS)
3. MODE $02 (POWERTRAIN FREEZE FRAME DATA)
Refer to data denoting the operating condition when trouble is detected by on-board diagnosis system.
A list of the support data and PID (Parameter Identification) codes are shown in the following table.
NOTE:
Refer to general scan tool manufacturer’s operation manual to access freeze frame data (MODE $02).
4. MODE $03 (EMISSION-RELATED POWERTRAIN DTC)
Refer to “List of Diagnostic Trouble Code (DTC)” for information about data denoting emission-related pow-
ertrain DTC.
5. MODE $04 (CLEAR/RESET EMISSION-RELATED DIAGNOSTIC INFORMATION)
Refer to the mode used to clear or reset emission-related diagnostic information (OBD-II trouble diagnostic
information).
NOTE:
Refer to general scan tool manufacturer's operation manual to clear or reset emission-related diagnostic in-
formation (MODE $04).
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 (Bank 1)%
07 Long term fuel trim (Bank 1)%
08 Short term fuel trim (Bank 2)%
09 Long term fuel trim (Bank 2)%
0B Intake manifold absolute pressure kPa
0C Engine speedrpm
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%
15 Oxygen sensor output voltage (Bank 1 Sensor 2) V
15 Oxygen sensor compensation (Bank 1 Sensor 2) %
16 Oxygen sensor output voltage (Bank 2 Sensor 2) V
16 Oxygen sensor compensation (Bank 2 Sensor 2) %
1C On-board diagnostic system—
EN(H6DO)(diag)-27
Subaru Select Monitor
ENGINE (DIAGNOSTICS)
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 has been displayed.
4) On the «Engine Diagnosis» display 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, scroll the display screen up or down until the desired data is shown.
•A list of the support data is shown in the following table.
Description Display Unit of measure Note (at idling)
Engine load Engine load % 3.5%
Engine coolant temperature signal Coolant Temp. °C or °F≥ 75°C or 167°F (After
engine is warmed-up.)
A/F compensation 1 A/F Compensation 1 % 3.1%
A/F learning 1 A/F learning 1 % 0.0%
A/F compensation 2 A/F Compensation 2 % 4.7%
A/F learning 2 A/F learning 2 % 0.0%
Intake manifold absolute pressure Mani. Absolute PressuremmHg, kPa,
inHg or psig
200 — 300 mmHg, 26.7 —
40 kPa, 7.8 — 11.8 inHg or
3.8 — 5.8 psig
Engine speed signal Engine speed rpm 600 — 800 rpm
Meter vehicle speed signal Meter vehicle speed km/h or MPH 0 km/h or 0 MPH
Ignition timing signal Ignition timing deg 13 — 15 deg
Intake air temperature signal Intake air temperature °C or °F (Ambient air temperature)
Amount of intake air Mass Air Flow g/s or lb/m 3.8 g/s or 0.5 lb/m
Throttle opening angle signal Throttle valve angle % 1.2 — 1.6%
Fr o nt ox yg e n se n so r vo lt a g e val ue 1Fr o n t oxy ge n s en s or vol t ag e
value 1V0.035 V
Fr o nt ox yg e n se n so r vo lt a g e val ue 2Fr o n t oxy ge n s en s or vol t ag e
value 2V0.020 V
Battery voltage Battery Voltage V 12 — 14 V
Mass air flow voltage Mass air flow voltage V 1.1 — 1.2 V
Injection 1 pulse width Injection 1 pulse width ms 2.82 ms
Injection 2 pulse width Injection 2 pulse width ms 2.82 ms
Knock sensor compensation Knock correction deg 0 deg
Atmospheric pressure signal Atmospheric pressuremmHg, kPa,
inHg or psig(Atmospheric pressure)
Intake manifold relative pressureIntake manifold relative pres-
sure
mmHg, kPa,
inHg or psig
(Intake manifold absolute
pressure — atmospheric
pressure)
Acceleration opening angle signal Acceleration opening angle % 0%
Radiator fan output Radiator fan output % 0%
Purge control solenoid valve duty ratio CPC Duty % 0 — 3%
Generator duty ALT duty % 0%
Fuel pump duty Fuel pump duty % 33%
Va r i a b l e va l v e t i m i n g a d v a n c e a n g l e a m o u n t R V V T a d va n c e a n g l e a m o u n t R d e g 0 d e g
Va r i a b l e va l v e t i m i n g a d v a n c e a n g l e a m o u n t L V V T a d va n c e a n g l e a m o u n t L d e g 0 d e g
Oil flow control solenoid valve duty R OCV duty R % 9.4%
Oil flow control solenoid valve duty L OCV duty L % 9.4%
Oil flow control solenoid valve current R OCV current R mA 64 mA
Oil flow control solenoid valve current L OCV current L mA 64 mA
Fr o nt ox yg e n ( A / F) s en so r cu r r en t va l ue 1 A / F s en s or cu r r e nt va l ue 1 mA 0 . 0 m A
Fr o nt ox yg e n ( A / F) s en so r cu r r en t va l ue 2 A / F s en s or cu r r e nt va l ue 2 mA 0 . 0 m A
Fr o nt ox yg e n ( A / F) s en so r r es is t an ce val ue 1 A / F s en s or r e si st a nc e val u e 1Ω31 Ω
EN(H6DO)(diag)-29
Subaru Select Monitor
ENGINE (DIAGNOSTICS)
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 has been 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 {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, scroll the display screen up or down until the desired data is shown.
•A list of the support data is shown in the following table.
AT c o o r d i n a t e f u e l c u t d e m a n d s i g n a l AT c o o r d i n a t e f u e l c u t d e m a n d — O F F
Ve h i c l e d y n a m i c s c o n t r o l ( V D C ) t o r q u e d o w n
prohibition outputBan of Torque Down — Permission
Ve h i c l e d y n a m i c s c o n t r o l ( V D C ) t o r q u e d o w n
demandVDC torque down demand — OFF
AT c o o r d i n a t e p e r m i s s i o n s i g n a l AT c o o r d i n a t e p e r m i s s i o n s i g n a l — P e r m i s s i o n
Electronic throttle control motor relay signal ETC motor relay — ON
Stop light switch signal Stop Light Switch — OFF
SET/COAST switch signal SET/COAST SW — OFF
RESUME/ACCEL switch signal RESUME/ACCEL SW — OFF
Brake switch signal Brake SW — OFF
Main switch signal Main SW — OFF
Body integrated unit data reception Body Int. Unit Data — Yes
Body integlated unit counter update Body Int. Unit Count — Yes
Cruise control cancel switch signal CC Cancel SW — OFF
Va r i a b l e v a l v e l i f t d i a g n o s i s o i l p r e s s u r e sw i t c h
signal 1Oil Temperature SW1 — ON
Va r i a b l e v a l v e l i f t d i a g n o s i s o i l p r e s s u r e sw i t c h
signal 2Oil Temperature SW2 — ON
Description Display Unit of measure
Number of diagnosis code Number of Diag. Codes: 0
Condition of malfunction indicator light MI (MIL) ON or OFF
Monitoring test of misfire Misfire monitoring Finish
Monitoring test of fuel system Fuel system monitoring Finish
Monitoring test of comprehensive component Component monitoring Finish
Te s t o f c a t a l y s t C a t a l y s t D i a g n o s i s F i n i s h o r i n c o m p l e t e
Te s t o f h e a t i n g - t y p e c a t a l y s t H e a t e d c a t a l y s t N o
Te s t o f e v a p o r a t i v e e m i s s i o n p u r g e c o n t r o l s y s t e m E v a p o r a t i v e p u r g e s y s t e m F i n i s h o r i n c o m p l e t e
Te s t o f s e c o n d a r y a i r s y s t e m S e c o n d a r y a i r s y s t e m N o
Te s t o f a i r c o n d i t i o n i n g s y s t e m r e f r i g e r a n t A / C s y s t e m r e f r i g e r a n t N o
Te s t o f o x y g e n s e n s o r O x y g e n s e n o r F i n i s h o r i n c o m p l e t e
Te s t o f o x y g e n s e n s o r h e a t e r O x y g e n s e n s o r h e a t e r F i n i s h
Te s t o f E G R s y s t e m E G R s y s t e m N o s u p p o r t
A/F control #1 Fuel system for Bank 1 OPEN early period
A/F control #2 Fuel system for Bank 2 OPEN early period
Calculated load valve Calculated load valve %
Engine coolant temperature Coolant Temp. °C
A/F compensation #1 Short term fuel trim B1 %
A/F learning #1 Long term fuel trim B1 %
A/F compensation #2 Short term fuel trim #2 %
A/F learning #2 Long term fuel trim B2 %
Description Display Unit of measure Note (at idling)
EN(H6DO)(diag)-31
Subaru Select Monitor
ENGINE (DIAGNOSTICS)
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 has been 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”.
Description Display Unit of measure
DTC of freeze frame data Freeze frame data DTC
Air fuel ratio control system for bank 1 Fuel system for Bank1 —
Air fuel ratio control system for bank 2 Fuel system for Bank2 —
Engine load data Engine Load %
Engine coolant temperature signal Coolant Temp. °C or °F
Short term fuel trim by front oxygen (A/F) sensor (Bank 1) Short term fuel trim B1 %
Long term fuel trim by front oxygen (A/F) sensor (Bank 1) Long term fuel trim B1 %
Short term fuel trim by front oxygen (A/F) sensor (Bank 2) Short term fuel trim B2 %
Long term fuel trim by front oxygen (A/F) sensor (Bank 2) Long term fuel trim B2 %
Intake manifold absolute pressure signal Mani. Absolute Pressure mmHg, kPa, inHg or psig
Engine speed signal Engine Speed rpm
Ve h i c l e s p e e d s i g n a l Ve h i c l e S p e e d k m / h o r M P H
Ignition timing #1 Ignition timing adv. #1 °
Intake air temperature Intake Air Temp. °C
Amount of intake air Mass Air Flow g/s
Throttle valve angle Throttle Opening Angle %
Oxygen sensor #12 Oxygen sensor #12 V
A/F compensation #12 Short term fuel trim #12 %
Oxygen sensor #22 Oxygen sensor #22 V
A/F compensation #12 Short term fuel trim #22 %
Oxygen sensor #11 Oxygen sensor #11 support
Oxygen sensor #12 Oxygen sensor #12 support
Oxygen sensor #21 Oxygen sensor #21 support
Oxygen sensor #22 Oxygen sensor #22 support