1995 SUBARU LEGACY ignition switch

OBD0727
1
CHECK IGNITION SYSTEM FOR SPARKS.
1) Remove plug cord cap from each spark plug.
2) Install new spark plug on plug cord cap.
CAUTION:
Do not remove spark plug from engine.
3) Contact spark plug’s thread portion on engine.
4) While opening throttle valve fully, crank engine to check
that spark occurs at each cylinder.
: Does spark occur at each cylinder?
: Check fuel pump system.
: Go to step 2.
OBD0123A
2CHECK POWER SUPPLY CIRCUIT FOR IGNI-
TION COIL.
1) Turn ignition switch to OFF.
2) Disconnect connector from ignition coil.
3) Turn ignition switch to ON.
4) Measure power supply voltage between ignition coil
connector terminal and body.
: Connector & terminal
(E12) No. 2—Body /10 V, or more
: Go to step 3.
: Repair harness between ignition coil and ignition
switch connector.
OBD0124
3
CHECK IGNITION COIL.
1) Measure resistance between ignition coil terminals to
check primary coil.
: Terminals
No. 2—No. 1/0.7±0.3Ω
No. 2—No. 3/0.7±0.3Ω
: Replace ignition coil.
: Go to next step.
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2-7ON-BOARD DIAGNOSTICS II SYSTEM
9. Diagnostics for Engine Starting Failure

OBD0125A
2) Measure resistance between spark plug cord contact
portions to check secondary coil.
: Connector & terminal
#1—#2 /21±3 kΩ
#3—#4 /21±3 kΩ
: Go to step 4.
: Replace ignition coil.
OBD0126A
4CHECK HARNESS CONNECTOR BETWEEN
IGNITOR AND IGNITION COIL.
1) Turn ignition switch to OFF.
2) Disconnect connector from ignitor.
3) Measure resistance of harness connector between igni-
tion coil and ignitor.
: Connector & terminal
(B13) No. 5—(E12) No. 1/10Ω, or less
(B13) No. 6—(E12) No. 3/10Ω, or less
: Go to step 5.
: Go to next.
: Is there poor contact in coupling connector
(B22)?
: Repair poor contact in coupling connector.
: Repair harness between ignition coil and ignitor
connector.
OBD0728
5
CHECK INPUT SIGNAL FOR IGNITOR.
Check if voltage varies synchronously with engine speed
when cranking, while monitoring voltage between ignitor
connector and body.
: Connector & terminal:
(B13) No. 1—Body/10 V, or more
(B13) No. 2—Body/10 V, or more
: Go to step 6.
: Replace ignitor.
B2M0224A
11 8
2-7ON-BOARD DIAGNOSTICS II SYSTEM
9. Diagnostics for Engine Starting Failure

OBD0128A
6CHECK HARNESS CONNECTOR OF IGNITOR
GROUND CIRCUIT.
1) Turn ignition switch to OFF.
2) Measure resistance between ignitor and body.
: Connector & terminal
(B13) No. 3—Body /10Ω, or less
: Go to step 7.
: Repair harness between ignitor connector and
body.
OBD0129A
7CHECK HARNESS CONNECTOR BETWEEN
ECM AND IGNITOR.
1) Disconnect connector from ECM.
2) Measure resistance of harness connector between
ECM and ignitor.
: Connector & terminal
(B84) No. 14—(B13) No. 1/10Ω, or less
(B84) No. 13—(B13) No. 2/10Ω, or less
(B84) No. 69—(B13) No. 3/10Ω, or less
: Repair open circuit of harness between ECM and
ignitor connector.
: Go to next step.
OBD0130A
3) Measure resistance of harness connector between
ECM and body.
: Connector & terminal
(B84) No. 13—Body/1 MΩ, or more
(B84) No. 14—Body/1 MΩ, or more
: Repair short circuit of harness between ECM and
ignitor.
: Confirm good connection in ECM connector.
11 9
2-7ON-BOARD DIAGNOSTICS II SYSTEM
9. Diagnostics for Engine Starting Failure

1
CHECK OPERATING SOUND OF FUEL PUMP.
Make sure that fuel pump is in operation for two seconds
when turning ignition switch to ON.
: Does fuel pump produce operating sound?
: Check fuel injector circuit.
: Go to step 2.
OBD0132A
2
CHECK GROUND CIRCUIT OF FUEL PUMP.
1) Turn ignition switch to OFF.
2) Disconnect connector from fuel pump.
3) Measure resistance of harness connector between fuel
pump and body.
: Connector & terminal
(R58) No. 4—Body /10Ω, or less
: Go to step 3.
: Repair open circuit of fuel pump ground circuit.
OBD0133A
3
CHECK POWER SUPPLY TO FUEL PUMP.
1) Turn ignition switch to ON.
2) Measure voltage of power supply circuit between fuel
pump connector and body.
: Connector & terminal
(R58) No. 1—Body /10 V, or more
: Replace fuel pump.
: Go to step 4.
OBD0134A
4CHECK HARNESS CONNECTOR BETWEEN
FUEL PUMP AND FUEL PUMP RELAY.
1) Turn ignition switch to OFF.
2) Measure resistance of harness connector between fuel
pump and fuel pump relay.
: Connector & terminal
(R58) No. 1—(B46) No. 4/10Ω, or less
: Go to next.
: Repair open circuit of harness between fuel pump
and fuel pump relay connector.
: Connector & terminal
(R58) No. 1—Body/1 MΩ, or more
: Go to step 5.
: Repair short circuit of harness between fuel pump
and fuel pump relay connector.
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2-7ON-BOARD DIAGNOSTICS II SYSTEM
9. Diagnostics for Engine Starting Failure

10. General Diagnostics Table
1. FOR ENGINE
12345678910111213
Problem parts
Mass air flow sensor
Engine coolant temperature sensor (*1)
Throttle position sensor
Crankshaft position sensor & Camshaft position sensor (*2)
Idle air control solenoid valve
Knock sensor
Purge control solenoid valve
EGR valve
Fuel injection parts (*3)
Ignition parts (*4)
Fuel pump and relay
A/C switch and A/C cut relay
Engine torque control signal circuitSymptom
1 Engine stalls during idling.   
2 Rough idling    
3 Engine does not return to idle.
4 Poor acceleration   
5Engine stalls or engine sags or hesi-
tates at acceleration.    
6 Surge   
7 Spark knock
8 After burning in exhaust system  
*1: The mark,, indicates the symptom occurring only in cold temperatures.
*2: For items with the mark,, ensure the secure installation of crankshaft position sensor and camshaft position sensor. Replacement is
not necessary.
*3: Check fuel injector, fuel pressure regulator and fuel filter.
*4: Check igniter, ignition coil and spark plug.
NOTE:
Malfunction of parts other than the above is also possible. Refer to 1. Engine Trouble in General [K100] in Repair Section 2-3 of the Ser-
vice Manual.
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2-7ON-BOARD DIAGNOSTICS II SYSTEM
10. General Diagnostics Table

OBD0145A
B2M0271
OBD0616
1CONNECT SUBARU SELECT MONITOR OR
THE OBD-II GENERAL SCAN TOOL, AND
READ DATA.
1) Turn ignition switch to OFF.
2) Connect Subaru Select Monitor or the OBD-II general
scan tool to data link connector.
3) Turn ignition switch to ON and Subaru Select Monitor or
the OBD-II general scan tool switch to ON.
4) Start engine.
5) Read data on Subaru Select Monitor or OBD-II general
scan tool.

Subaru Select Monitor
Designate mode using function key.
Function mode: F08 or F47

F08: Voltage input from mass air flow sensor is shown
on display.

F47: Mass air flow is shown on display.

F08: Is sensor output equal to or more
than 0.3 V and equal to or less than
5.0 V?

F47: Is sensor output equal to or more
than 1.3 g/sec and equal to or less
than 250 g/sec?
Probable cause: Poor connect of connectors, circuit and
grounding line.
: Even if MIL lights up, the circuit has returned to a
normal condition at this time. A temporary poor
contact of the connector or harness may be the
cause. Repair harness or connector of the mass
air flow sensor.
HINT:
1Open or short circuit between mass air flow sen-
sor and ECM.

2Poor contact of connectors for mass air flow sen-
sor or ECM.
: Go to next.
: Is the value less than 0.3 V (1.3 g/sec)?
: Go to step 2.
: Go to step 5.

OBD-II general scan tool
For detailed operation procedures, refer to the OBD-II Gen-
eral Scan Tool Instruction Manual.
138
2-7ON-BOARD DIAGNOSTICS II SYSTEM
11. Diagnostics Chart with Trouble Code

OBD0689A
2CHECK INPUT SIGNAL FOR ECM. (USING
VOLTAGE METER AND SUBARU SELECT
MONITOR.)
Measure voltage between ECM and body while engine is
idling.
: Connector & terminal
(B84) No. 26—Body/0.3 V, or less
: Go to step 3.
: Go to next.
G2M0527
: Is the voltage more than 0.3 V while shaking
harness and connector of ECM and monitor-
ing the value with Subaru select monitor?
: Repair poor contact in ECM connector.
: Replace ECM with a new one.
B2M0623A
3CHECK POWER SUPPLY TO MASS AIR
FLOW SENSOR.
1) Turn ignition switch to OFF.
2) Disconnect connector from mass air flow sensor.
3) Turn ignition switch to ON.
4) Measure voltage between mass air flow sensor connec-
tor and body.
: Connector & terminal
(B3) No. 1—Body/10 V, or more
: Go to step 4.
: Repair open circuit of harness between main relay
connector and mass air flow sensor connector.
139
2-7ON-BOARD DIAGNOSTICS II SYSTEM
11. Diagnostics Chart with Trouble Code

OBD0690A
4CHECK HARNESS CONNECTOR BETWEEN
ECM AND MASS AIR FLOW SENSOR.
1) Turn ignition switch to OFF.
2) Disconnect connector from ECM.
3) Measure resistance of harness connector between
ECM and mass air flow sensor.
: Connector & terminal

1(B84) No. 26—(B3) No. 4/10Ω, or less

2(B84) No. 46—(B3) No. 3/10Ω, or less

3(B84) No. 25—(B3) No. 2/10Ω, or less
: Replace mass air flow sensor with a new one.
: Repair poor contact and open circuit of harness
between ECM and mass air flow sensor connec-
tor.
G2M0527
5
CHECK HARNESS.
1) Turn ignition switch to OFF.
2) Disconnect connector from mass air flow sensor.
3) Connect Subaru Select Monitor or OBD-II General
Scan Tool to data link connector.
4) Turn ignition switch to ON.
5) Read data on Subaru select monitor or OBD-II general
scan tool.

Subaru Select Monitor
Designate mode using function key.
Function mode: F08
: Is the value more than 5 V?
: Repair short circuit of harness between mass air
flow sensor and ECM.
: Go to next.
: Is there poor contact in mass air flow sensor
connector?
: Repair poor contact in mass air flow sensor con-
nector.
: Replace mass air flow sensor.

OBD-II general scan tool
For detailed operation procedures, refer to OBD-II General
Scan Tool Instruction Manual.
140
2-7ON-BOARD DIAGNOSTICS II SYSTEM
11. Diagnostics Chart with Trouble Code