ENGINE MALFUNCTION INDICATOR LAMP (MIL)
Engine (Diagnostics)
11. Engine Malfunction Indicator Lamp (MIL)
S068653
A: PROCEDURE
S068653E45
1. Activation of check engine malfunction indicator lamp (MIL). <Ref. to EN(SOHCw/oOBD)-33 ACTIVATION OF CHECK ENGINE MALFUNCTION INDICATOR LAMP (MIL), Engine Malfunction Indicator Lamp (MIL).>
2. Check engine malfunction indicator lamp (MIL) does not come on. <Ref. to EN(SOHCw/oOBD)-34 CHECK ENGINE MAL-FUNCTION INDICATOR LAMP (MIL) DOES NOT COME ON., Engine Malfunction Indicator Lamp (MIL).>
3. Check engine malfunction indicator lamp (MIL) does not go off. <Ref. to EN(SOHCw/oOBD)-38 CHECK ENGINE MAL­FUNCTION INDICATOR LAMP (MIL) DOES NOT GO OFF., Engine Malfunction Indicator Lamp (MIL).
4. Check engine malfunction indicator lamp (MIL) does not blink at a cycle of 3 Hz. <Ref. to EN(SOHCw/oOBD)-40 CHECK ENGINE MALFUNCTION INDICATOR LAMP (MIL) DOES NOT BLINK AT A CYCLE OF 3 HZ., Engine Malfunction Indicator Lamp (MIL).>
5. Check engine malfunction indicator lamp (MIL) remains blinking at a cycle of 3 Hz. <Ref. to EN(SOHCw/oOBD)-44 CHECK ENGINE MALFUNCTION INDICATOR LAMP (MIL) REMAINS BLINKING AT A CYCLE OF 3 HZ., Engine Malfunction Indicator Lamp (MIL).>
B: ACTIVATION OF CHECK ENGINE MALFUNCTION INDICATOR LAMP
?MI L ) f S068653E89
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 circuit. <Ref. to I DI-1 5 Combination Meter Assembly.>
2) After starting the engine, the MIL goes out. If it does not, either the engine or the emission control system is malfunctioning. <Ref. to EN(SOHCw/ oOBD)-2 PROCEDURE, Basic Diagnostic Proce­dure.>
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3) 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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EN(SOHCw/oOBD)-33
Engine (Diagnostics)
ENGINE MALFUNCTION INDICATOR LAMP (MIL)
C: CHECK ENGINE MALFUNCTION INDICATOR LAMP (MIL) DOES NOT
COME ON.
S068653E90
  DIAGNOSIS:
•  The CHECK ENGINE malfunction indicator lamp (MIL) circuit is open or shorted.
•  TROUBLE SYMPTOM:
•  When ignition switch is turned ON (engine OFF), MIL does not come on.
•  WIRING DIAGRAM:
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EN(SOHCw/oOBD)-34
ENGINE MALFUNCTION INDICATOR LAMP (MIL)
Engine (Diagnostics)
No.
Step
Check
Yes
No
1
CHECK OUTPUT SIGNAL FROM ECM.
1) Disconnect connector from ECM, then con­nect check board. <Ref. to EN(SOHCw/ oOBD)-23, HOW TO CHECK I/O SIGNAL FOR ECM, Engine Control Module (ECM) I/O Signal.> 2) Turn ignition switch to ON. 3) Measure voltage between ECM connector and engine ground. Connector & terminal (C) No. 40 (+) - Engine ground (-):
Is the voltage less than 1 V?
Go to step 4.
Go to step 2.
2
CHECK POOR CONTACT.
Does the MIL come on when shaking or pulling ECM connector and har­ness?
Repair poor con­tact in ECM con­nector.
Go to step 3.
3
CHECK ECM CONNECTOR.
Is ECM connector correctly connected?
Replace ECM. <Ref. to FU(SOHCw/ oOBD)-38, Engine Control Module.>
Repair connection of ECM connec­tor.
4
CHECK HARNESS BETWEEN COMBINA­TION METER AND ECM CONNECTOR.
1) Turn ignition switch to OFF. 2) Remove combination meter. <Ref. to IDI-15, Combination Meter Assembly.> 3) Disconnect connector from ECM and com­bination meter. 4) Measure resistance of harness between ECM and combination meter connector. Connector & terminal (B84) No. 13 - (i10) No. 9:
Is resistance less than 1 Q?
Go to step 5.
Repair harness and connector. NOTE: In this case, repair the follow­ing: • Open circuit in harness between ECM and combi­nation meter con­nector • Poor contact in coupling connec­tor (i2)
5
CHECK POOR CONTACT.
Check poor contact in combination meter connec­nector. <Ref. to IDI-15, Combination Meter Assembly. >
Is there poor contact in combination meter connec­tor?
Repair poor con­tact in combina­tion meter con­nector.
Go to step 6.
EN(SOHCw/oOBD)-35
Engine (Diagnostics)
ENGINE MALFUNCTION INDICATOR LAMP (MIL)
No.
Step
Check
Yes
No
6
CHECK HARNESS BETWEEN COMBINA-
Is voltage more than 10 V?
Go to step 7.
Check the follow-
TION METER AND IGNITION SWITCH CON-
ing and repair if
NECTOR.
necessary.
1) Turn ignition switch to ON.
NOTE:
2) Measure voltage between combination
• Broken down
meter connector and chassis ground.
ignition relay.
Connector & terminal
• Blown out fuse
(i10) No. 2 (+) - Chassis ground (-):
(No. 5).
• If replaced fuse
(No. 5) blows
easily, check the
harness for short
circuit of harness
between fuse (No.
5) and ignition
relay connector.
• Open or short
circuit in harness
between fuse (No.
5) and battery ter-
minal
• Open circuit in
harness between
fuse (No. 5) and
ignition relay con-
nector
• Poor contact in
coupling connec-
tor (i1)
• Poor contact in
ignition relay con-
nector
• Poor contact in
ignition switch
connector
7
CHECK POOR CONTACT.
Is there poor contact in
Repair poor con-
Replace bulb or
Check poor contact in combination meter connec-
combination meter connec-
tact in combina-
combination
nector. <Ref. to IDI-15, Combination Meter
tor?
tion meter con-
meter.
Assembly. >
nector.
EN(SOHCw/oOBD)-36
ENGINE MALFUNCTION INDICATOR LAMP (MIL)
Engine (Diagnostics) MEMO:
EN(SOHCw/oOBD)-37
Engine (Diagnostics)
ENGINE MALFUNCTION INDICATOR LAMP (MIL)
D: CHECK ENGINE MALFUNCTION INDICATOR LAMP (MIL) DOES NOT GO
OFF.
S068653E91
  DIAGNOSIS:
•  The CHECK ENGINE malfunction indicator lamp (MIL) circuit is shorted.
•  TROUBLE SYMPTOM:
•  Although MIL comes on when engine runs, trouble code is not shown on Subaru select monitor or OBD-II general scan tool display.
•  WIRING DIAGRAM:
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No.
Step
Check
Yes
No
1
CHECK HARNESS BETWEEN COMBINA­TION METER AND ECM CONNECTOR.
1) Turn ignition switch to OFF.
2)  Disconnect connector from ECM.
3) Turn ignition switch to ON.
Does the MIL come on?
Repair short cir­cuit in harness between combina­tion meter and ECM connector.
Replace ECM. <Ref. to FU(SOHCw/ oOBD)-38, Engine Control Module.>
EN(SOHCw/oOBD)-38
ENGINE MALFUNCTION INDICATOR LAMP (MIL)
Engine (Diagnostics) MEMO:
EN(SOHCw/oOBD)-39
ENGINE MALFUNCTION INDICATOR LAMP (MIL)
Engine (Diagnostics)
E: CHECK ENGINE MALFUNCTION INDICATOR LAMP (MIL) DOES NOT
BLINK AT A CYCLE OF 3 Hz.
S068653E92
  DIAGNOSIS:
•  The CHECK ENGINE malfunction indicator lamp (MIL) circuit is open or shorted.
•  Test mode connector circuit is in open.
•  TROUBLE SYMPTOM:
•  When inspection mode, MIL does not blink at a cycle of 3 Hz.
EN(SOHCw/oOBD)-40
ENGINE MALFUNCTION INDICATOR LAMP (MIL)
Engine (Diagnostics)
• WIRING DIAGRAM:
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No.
Step
Check
Yes
No
1
CHECK STATUS OF CHECK ENGINE MAL-
Does the MIL come on?
Go to step 2.
Repair the MIL
FUNCTION INDICATOR LAMP (MIL).
circuit. <Ref. to
1) Turn ignition switch to OFF.
EN(SOHCw/
2) Disconnect test mode connector.
oOBD)-34,
3) Turn ignition switch to ON.
CHECK ENGINE
MALFUNCTION
INDICATOR
LAMP (MIL)
DOES NOT
COME ON.,
Engine Malfunc-
tion Indicator
Lamp (MIL).>
EN(SOHCw/oOBD)-41
Engine (Diagnostics)
ENGINE MALFUNCTION INDICATOR LAMP (MIL)
No.
Step
Check
Yes
No
2
CHECK OUTPUT SIGNAL FROM ECM.
Measure voltage between test mode connec­tor and chassis ground. Connector & terminal (B75) No. 1 (+) - Chassis ground (-):
Is voltage less than 1 V?
Go to step 3.
Go to step 5.
3
CHECK HARNESS BETWEEN ECM AND TEST MODE CONNECTOR.
1) Turn ignition switch to OFF. 2) Disconnect connector from ECM. 3) Measure resistance of harness between ECM and test mode connector. Connector & terminal (B84) No. 19 - (B75) No. 1:
Is resistance less than 1 Q?
Go to step 4.
Repair harness and connector. NOTE: In this case, repair the follow­ing: • Open circuit in harness between ECM and test mode connector • Poor contact in coupling connec­tor (B180)
4
CHECK POOR CONTACT.
Check poor contact in ECM connector.
Is there poor contact in ECM connector?
Repair poor con­tact in ECM con­nector.
Replace ECM. <Ref. to FU(SOHCw/ oOBD)-38, Engine Control Module.>
5
CHECK HARNESS BETWEEN ECM AND TEST MODE CONNECTOR.
1) Turn ignition switch to OFF. 2) Disconnect connector from ECM. 3) Measure resistance of harness between ECM and test mode connector. Connector & terminal (B84) No. 15 - (B76) No. 1:
Is resistance less than 1 Q?
Go to step 6.
Repair harness and connector. NOTE: In this case, repair the follow­ing: • Open circuit in harness between ECM and test mode connector • Poor contact in coupling connec­tor (B138)
6
CHECK POOR CONTACT.
Check poor contact in ECM connector.
Is there poor contact in ECM connector?
Repair poor con­tact in ECM con­nector.
Replace ECM. <Ref. to FU(SOHCw/ oOBD)-38, Engine Control Module.>
EN(SOHCw/oOBD)-42
ENGINE MALFUNCTION INDICATOR LAMP (MIL)
Engine (Diagnostics) MEMO:
EN(SOHCw/oOBD)-43
Engine (Diagnostics)
ENGINE MALFUNCTION INDICATOR LAMP (MIL)
F: CHECK ENGINE MALFUNCTION INDICATOR LAMP (MIL) REMAINS
BLINKING AT A CYCLE OF 3 Hz.
S068653E93
  DIAGNOSIS:
•  Test mode connector circuit is shorted.
•  TROUBLE SYMPTOM:
•   Even though test mode connector is disconnected, MIL blinks at a cycle of 3 Hz when ignition switch is turned to ON.
•  WIRING DIAGRAM:
for_01_21-367.jpg
EN(SOHCw/oOBD)-44
ENGINE MALFUNCTION INDICATOR LAMP (MIL)
Engine (Diagnostics)
No.
Step
Check
Yes
No
1
CHECK HARNESS BETWEEN ECM CON-
Is resistance less than 5
Repair short cir-
Replace ECM.
NECTOR AND ENGINE GROUNDING TER-
Q?
cuit in harness
<Ref. to
MINAL.
between ECM
FU(SOHCw/
1) Turn ignition switch to OFF.
and test mode
oOBD)-38, Engine
2) Disconnect connector from ECM.
connector.
Control Module.>
3) Measure resistance of harness between
ECM connector and engine ground.
Connector & terminal
(B84) No. 19 - Engine ground:
EN(SOHCw/oOBD)-45
ENGINE MALFUNCTION INDICATOR LAMP (MIL)
Engine (Diagnostics) MEMO:
EN(SOHCw/oOBD)-46