Mitsubishi Electric Lancer Evolution-VII Workshop Manual page 1237

13A-100
Inspection Procedure 32
Ignition coil (integrated power transistor) system
The engine-ECU allows the ignition coil primary current to flow intermittently by
turning the power transistor in the unit OFF and ON.
Check the spark plug cable.
(Refer to GROUP 16 - Ignition Device.)
OK
Check the spark plug.
(Refer to GROUP 16 - Ignition Device.)
OK
Check the following connectors:
B-114, B-119
OK
Check the ignition coil.
(Refer to GROUP 16 - Ignition Device.)
OK
Measure at the B-119 and B-123
ignition coil connectors.
D Disconnect the connector to
measure at the harness side.
(1) Voltage between terminal No. 1 and
earth
(Ignition switch: ON)
OK: System voltage
(2) Voltage between terminal No. 3 and
earth
(Engine: Cranking)
OK: 0.5 - 4.0 V
(3) Resistance between terminal No. 2
and earth
OK: 2 Ω or less
OK
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MPI -
Troubleshooting
NG
Replace the spark plug cable.
NG
Replace the spark plug.
NG
Repair
OK
Replace the ignition coil.
(1) NG
Check the following connector:
B-09X
Check the ignition coil relay.
(Refer to GROUP 16 - Engine
Electrical.)
Check and repair the harness between
the ignition coil and ignition coil relay.
D Check for short-circuit of the power
cable.
(2) NG
Measure at the C-126 engine-ECU
connector.
D Measure the engine-ECU terminal
voltage.
D Disconnect the connectors B-114
and B-119.
D Engine: Cranking
(1) Voltage between terminal No. 10,
terminal No. 23 and earth
Check the following connector:
C-126
Check the harness between the
ignition coil and engine-ECU.
D Check for disconnection of the
output cable.
Check the trouble symptoms.
Replace the engine-ECU.
(3) NG
Check and repair the harness between
the ignition coil and body earth.
D Check for disconnection and
damage of the earth cable.
Probable cause
D Ignition coil malfunction
D Spark plug malfunction
D Spark plug cable malfunction
D Ignition primary circuit disconnection, short-circuit, or
connector contact defect
D Engine-ECU malfunction
NG
OK
OK
OK
NG
NG
OK
NG
OK
OK
NG
Repair
Check the following connector:
C-126
OK NG
Repair
Check and repair the harness between
the ignition coil and engine-ECU.
D Check for disconnection of the
output cable.
Repair
Repair
Intermittent malfunction
(Refer to GROUP 00 - Points to Note
for Intermittent Malfunctions.)