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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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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).
29
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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
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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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OBD0057A
C: SUBARU SELECT MONITOR
1. HOW TO USE SUBARU SELECT MONITOR
1) Prepare Subaru select monitor and cartridge.
ST1 498307500 SELECT MONITOR KIT
ST2 498349601 CARTRIDGE
G3M0150
2) Turn ignition switch and Subaru select monitor switch to
OFF.
3) Insert cartridge into Subaru select monitor.
OBD0059A
4) Connect Subaru select monitor to data link connector.
Using data link connector for Subaru select monitor
only, connect Subaru select monitor to its data link con-
nector located in the lower portion of the instrument
panel (on the driver’s side), to the side of the center
console box.
OBD0669A
Using data link connector for Subaru select monitor
and OBD-II general scan tool;
(1) Connect ST to Subaru select monitor cable.
ST 498357200 ADAPTER CABLE
OBD0006C
(2) Open the cover and connect Subaru select monitor
to data link connector located in the lower portion of the
instrument panel (on the driver’s side), to the lower
cover.
CAUTION:
Do not connect scan tools except for Subaru select
monitor and OBD-II general scan tool.
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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].
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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.
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2-7ON-BOARD DIAGNOSTICS II SYSTEM
3. Diagnosis System