1995 SUBARU LEGACY engine

OBD0008C
3. Diagnosis System
A: MALFUNCTION INDICATOR LAMP (MIL)
1. ACTIVATION OF MALFUNCTION INDICATOR LAMP
(MIL)
1) When ignition switch is turned to ON (engine off), the
CHECK ENGINE malfunction indicator lamp (MIL) in the
combination meter illuminates.
NOTE:
If the MIL does not illuminate, perform diagnostics of the
CHECK ENGINE light circuit or the combination meter cir-
cuit. function Indicator Lamp (MIL) [T800]”.>
OBD0053A
2) After starting the engine, the MIL goes out. If it does not,
either the engine or the emission control system is mal-
functioning.
OBD0054A
3) If the diagnosis system senses a misfire which could
damage the catalyzer, the MIL will blink at a cycle of 1 Hz.
OBD0055A
4) When ignition switch is turned to ON (engine off) or to
“START” with the test mode connector connected, the MIL
blinks at a cycle of 3 Hz.
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2-7ON-BOARD DIAGNOSTICS II SYSTEM
3. Diagnosis System

3. READ DATA LIST

MODE $01
—Current powertrain diagnostic data—
Refers to data denoting the current operating condition of
analog input/output, digital input/output and/or the power-
train system.
A list of the support data and PID (Parameter Identification)
codes are shown in the following table.
PID DataUnit of measure
01 Number of emission-related powertrain trouble codes and MIL status ON/OFF
03 Fuel system control status—
04 Calculated engine load value%
05 Engine coolant temperature°C
06 Short term fuel trim%
07 Long term fuel trim%
0B Intake manifold absolute pressurekPa
0C Engine revolutionrpm
0D Vehicle speedkm/h
0E Ignition timing advance°
10 Air flow rate from mass air flow sensor g/sec
11 Throttle valve opening angle%
13 Check whether oxygen sensor is installed.—
14 Oxygen sensor output voltage and short term fuel trim associated with oxygen sensor—bank 1 V and %
15 Oxygen sensor output voltage and short term fuel trim associated with oxygen sensor—bank 2 V and %
1C On-board diagnosis system—
NOTE:
Refer to OBD-II general scan tool manufacturer’s instruc-
tion manual to access generic OBD-II PIDs (MODE $01).
29
2-7ON-BOARD DIAGNOSTICS II SYSTEM
3. Diagnosis System

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.
PID DataUnit of measure
02 Trouble code 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 fuel trim%
0B Intake manifold absolute pressurekPa
0C Engine revolutionrpm
0D Vehicle speedkm/h
NOTE:
Refer to OBD-II general scan tool manufacturer’s instruc-
tion manual to access freeze frame data (MODE $02).

MODE $03
—Emission-related powertrain diagnostic
trouble codes—
Refers to data denoting emission-related powertrain diag-
nostic trouble codes.
For details concerning diagnostic trouble codes, refer to
the DIAGNOSTIC TROUBLE CODE (DTC) LIST [T11A0].
NOTE:
Refer to OBD-II general scan tool manufacturer’s instruc-
tion manual to access emission-related powertrain diag-
nostic trouble codes (MODE $03).
30
2-7ON-BOARD DIAGNOSTICS II SYSTEM
3. Diagnosis System

OBD0060
5) Turn ignition switch ON (engine OFF) and Subaru
select monitor switch ON.
OBD0064
6) Using Subaru select monitor, call up diagnostic trouble
code(s) and various data, then record them.

READ DIAGNOSTIC TROUBLE CODE (DTC) SHOWN
ON DISPLAY. (MODE FB1)
(1) Press the function key [0].
G3M0152
(2) Designate mode using function key.
Press [F] [B] [1] [ENT] in that order.
OBD0062
(3) Ensure diagnostic trouble code(s) is shown.

When there is only one diagnostic trouble code.
OBD0063

When there are multiple diagnostic trouble codes.
NOTE:
For details concerning diagnostic trouble codes, refer to
the DIAGNOSTIC TROUBLE CODE (DTC) LIST [T11A0].
33
2-7ON-BOARD DIAGNOSTICS II SYSTEM
3. Diagnosis System

OBD0064

READ CURRENT DATA AND FREEZE FRAME DATA
SHOWN ON DISPLAY FOR ENGINE. (FUNCTION
MODE)
(1) Press the function key [0].
G3M0152
(2) Designate mode using function key.
Refer to“READ DATA FUNCTION KEY LIST FOR
ENGINE”[T3C2].
(Example: Press [F] [0] [1] [ENT] in that order.)
(3) Ensure data of input or output signal is shown.
OBD0461

READ CURRENT DATA SHOWN ON DISPLAY FOR
AT. (FUNCTION MODE)
(1) Press the function key [/], and change to AT mode.
OBD0462
(2) Press the function key [0].
G3M0152
(3) Designate mode using function key.
Refer to“READ DATA FUNCTION KEY LIST FOR AT”
[T3C6].
(Example: Press [F] [0] [2] [ENT] in that order.)
(4) Ensure data of input or output signal is shown.
34
2-7ON-BOARD DIAGNOSTICS II SYSTEM
3. Diagnosis System

2. READ DATA FUNCTION KEY LIST FOR ENGINE
Function mode Contents Abbreviation Unit of measure
F00 ROM ID number YEAR—
F01 Battery voltage VB V
F02 Vehicle speed signal VSP m/h
F03 Vehicle speed signal VSP km/h
F04 Engine speed signal EREV rpm
F05 Engine coolant temperature signal TW°F
F06 Engine coolant temperature signal TW°C
F07 Ignition signal ADVS deg
F08 Mass air flow signal QA V
F09 Load data DATA—
F10 Throttle position signal THV V
F11 Injector pulse width TIM mS
F12 Idle air control signal ISC %
F13 Front oxygen sensor output signal FO2 V
F14 Front oxygen sensor maximum output signal FO2max V
F15 Front oxygen sensor minimum output signal FO2min V
F16 Rear oxygen sensor output signal RO2 V
F17 Rear oxygen sensor maximum output signal RO2max V
F18 Rear oxygen sensor minimum output signal RO2min V
F19 Short term fuel trim ALPHA %
F20 Knock sensor signal RTRD deg
F21 A/F correction (short term trim) by rear oxygen sensor PHOS %
F23 Atmospheric absolute pressure signal (AT vehicles) BARO. P V
F24 Intake manifold absolute pressure signal (AT vehicles) MANI. P V
F25 Long term fuel trim KBLRC %
F28 Long term whole fuel trim K0 %
F29 Front oxygen sensor heater current FO2H A
F30 Rear oxygen sensor heater current RO2H A
F33Maximum value of cylinder #1 misfire times during 200
rotationsMF1 %
F34Maximum value of cylinder #2 misfire times during 200
rotationsMF2 %
F35Maximum value of cylinder #3 misfire times during 200
rotationsMF3 %
F36Maximum value of cylinder #4 misfire times during 200
rotationsMF4 %
F37 Maximum EGR system pressure value (AT vehicles) EGRmax mmHg
F38 Minimum EGR system pressure value (AT vehicles) EGRmin mmHg
F45 Load data LOAD %
F46 Throttle position signal THV %
F47 Mass air flow signal QA g/s
F48 Atmospheric absolute pressure signal BARO. P kPa
F49 Intake manifold absolute pressure signal MANI. P kPa
35
2-7ON-BOARD DIAGNOSTICS II SYSTEM
3. Diagnosis System

Function mode Contents Abbreviation Unit of measure
F50 Load data (Freeze frame data) LOADF %
F51 Engine coolant temperature signal (Freeze frame data) TWF °C
F52 Short term fuel trim (Freeze frame data) ALPHF %
F53 Long term fuel trim (Freeze frame data) KBLRF %
F54Intake manifold absolute pressure signal (Freeze frame
data) MANIF kPa
F55 Engine speed signal (Freeze frame data) EREVF rpm
F56 Vehicle speed signal (Freeze frame data) VSPF km/h
FA 0 O N)OFF signal — —
FA 1 O N)OFF signal — —
FA 2 O N)OFF signal — —
FA 3 O N)OFF signal — —
FA 4 O N)OFF signal — —
FB0 Diagnostic trouble code (DTC) INSPECT —
FB1 Diagnostic trouble code (DTC) OBD —
FC0 Clear memory — —
NOTE:
1) Subaru select monitor is also available for monitoring
information other than that used for check and repair of the
vehicle.
2) The maximum values shown for F33, F34, F35 and F36
do not indicate the actual cylinder misfire rate.
36
2-7ON-BOARD DIAGNOSTICS II SYSTEM
3. Diagnosis System

G2M0523

FUNCTION MODE: F02 AND F03
—VEHICLE SPEED SIGNAL (VSP)—

F02: Vehicle speed is indicated in mile per hour (MPH).

F03: Vehicle speed is indicated in kilometer per hour
(km/h).
G2M0524

FUNCTION MODE: F04
—ENGINE SPEED SIGNAL (EREV)—
OBD0176

FUNCTION MODE: F05 AND F06
—ENGINE COOLANT TEMPERATURE
SIGNAL (TW)—

F05: Engine coolant temperature is indicated in“°F”.

F06: Engine coolant temperature is indicated in“°C”.
G2M0654

FUNCTION MODE: F07
—IGNITION SIGNAL (ADVS)—
NOTE:
The ignition timing value displayed in mode F07 is a value
computed by ECM and will not always correspond with the
value measured with a timing light.
B2M0271

FUNCTION MODE: F08
—MASS AIR FLOW SIGNAL (QA)—
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2-7ON-BOARD DIAGNOSTICS II SYSTEM
3. Diagnosis System