OBD SUBARU LEGACY 1995 Service Owner's Manual

2. MODULE (RHD MODEL)
B2M0430C
1Transmission Control Module (TCM)2AT diagnostic indicator light
B2M0436AOBD0008B
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2. Electrical Components Location

3. SENSOR (LHD MODEL)
OBD0041AOBD0042A
OBD0043AOBD0044A
H2M1145COBD0653A
1Vehicle speed sensor 1 (for AT FWD vehicles)

2Vehicle speed sensor 1 (for AT AWD vehicles)

3Vehicle speed sensor 2 (for MT vehicles)
4Vehicle speed sensor 2 (for AT vehicles)

5ATF temperature sensor (for AT vehicles)

6Brake light switch
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2-7ON-BOARD DIAGNOSTICS II SYSTEM
2. Electrical Components Location

4. SENSOR (RHD MODEL)
OBD0042BOBD0044B
B2M0464AB2M0437A
1Vehicle speed sensor 1

2Vehicle speed sensor 2
3ATF temperature sensor

4Brake light switch
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2-7ON-BOARD DIAGNOSTICS II SYSTEM
2. Electrical Components Location

5. SOLENOID VALVE AND RELAY

For AT vehicles
OBD0046BOBD0047B
OBD0048AOBD0049A
1Dropping resistor

2Inhibitor switch

3Shift solenoid valve 1

4Shift solenoid valve 2
5Shift solenoid valve 3

6Duty solenoid valve A

7Duty solenoid valve B
OBD0050A
8Duty solenoid valve C (AWD models)
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2-7ON-BOARD DIAGNOSTICS II SYSTEM
2. Electrical Components Location

For MT vehicles
OBD0051AOBD0526A
1Neutral position switch (FWD models)2Neutral position switch (AWD models)
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2-7ON-BOARD DIAGNOSTICS II SYSTEM
2. Electrical Components Location

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

OBD0006C
B: OBD-II GENERAL SCAN TOOL
1. HOW TO USE OBD-II GENERAL SCAN TOOL
1) Prepare a general scan tool (OBD-II general scan tool)
required by SAE J1978.
2) Open the cover and connect the OBD-II general scan
tool to the data link connector located in the lower portion
of the instrument panel (on the driver’s side), to the lower
cover.
3) Using the OBD-II general scan tool, call up diagnostic
trouble code(s) and freeze frame data.
OBD-II general scan tool functions consist of:
(1) MODE $01: Current powertrain diagnostic data
(2) MODE $02: Powertrain freeze frame data
(3) MODE $03: Emission-related powertrain diagnostic
trouble codes
(4) MODE $04: Clear/Reset emission-related diagnos-
tic information
(5) MODE $05: Oxygen sensor monitoring test results
Read out data according to repair procedures.
(For detailed operation procedures, refer to the OBD-II
General Scan Tool Operation Manual.)
NOTE:
For details concerning diagnostic trouble codes, refer to
the DIAGNOSTIC TROUBLE CODE (DTC) LIST [T11A0].
H2M1280
2. DATA LINK CONNECTOR (FOR OBD-II GENERAL
SCAN TOOL AND SUBARU SELECT MONITOR)
1) This connector is used both for OBD-II general scan
tools and Subaru Select Monitor.
2) Terminal No. 4 to No. 6 of data link connector is used
for Subaru Select Monitor signal.
CAUTION:
Do not connect scan tools other than OBD-II general
scan tools and Subaru Select Monitor, because the
circuit for Subaru Select Monitor may be damaged.
Terminal No. Contents Terminal No. Contents
1 Power supply 9 Blank
2 Blank10 K line of ISO 9141 CARB
3 Blank11 Blank
4 Subaru Select Monitor signal (ECM to Subaru Select monitor)* 12 Ground
5 Subaru Select Monitor signal (Subaru Select monitor to ECM)* 13 Ground
6 Subaru Select Monitor clock* 14 Blank
7 Blank15 Blank
8 Blank16 Blank
*: Circuit only for Subaru Select Monitor
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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).
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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).
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2-7ON-BOARD DIAGNOSTICS II SYSTEM
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MODE $04
—Clear/Reset emission-related diagnostic information—
Refers to the mode used to clear or reset emission-related
diagnostic information (OBD-II trouble diagnostic informa-
tion).
NOTE:
Refer to OBD-II general scan tool manufacturer’s instruc-
tion manual to clear or reset emission-related diagnostic
information (MODE $04).

MODE $05
—Oxygen sensor monitoring test results—
Refers to the mode using oxygen sensor output data while
the on-board diagnosis system is performing diagnosis on
the oxygen sensor.
A list of the support oxygen sensor output data and test ID
(identification) are shown in the following table.
Test ID DataUnit of measure
01 Rich to lean sensor threshold voltage (constant) V
02 Lean to rich sensor threshold voltage (constant) V
03 Low sensor voltage for switch time calculation (constant) V
04 High sensor voltage for switch time calculation (constant) V
05 Rich to lean sensor switch time (calculated) sec.
06 Lean to rich sensor switch time (calculated) sec.
07 Minimum sensor voltage for test cycle (calculated) V
08 Maximum sensor voltage for test cycle (calculated) V
NOTE:
Refer to OBD-II general scan tool manufacturer’s instruc-
tion manual to access oxygen sensor monitoring test
results (MODE $05).
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3. Diagnosis System