Mitsubishi FUEL Manual page 68

13A-68
INSPECTION PROCEDURE 26
Engine-ECU <M/T> or engine-A/T-ECU <A/T> power
supply and earth circuit system
The engine-ECU <M/T> or engine-A/T-ECU <A/T> may be defective, or that one
of the malfunctions listed at right has occurred.
Measure at the engine-ECU connectors C-34, C-36, C-40
<M/T> or the engine-A/T-ECU connectors C-175, C-176 <A/T>.
D Disconnect the connector and measure at the harness side
(1) Voltage between 82 <M/T>, 98 <A/T> and earth (Ignition
switch: ON)
OK: System voltage
(2) Voltage between 38 <M/T>, 49 <A/T> and earth
OK: System voltage
(3) Voltage between 12, 25 <M/T> 41, 47 <A/T> and earth
(Ignition switch: ON)
OK: System voltage (when the terminal 38 <M/T>, 49 <A/T>
is earthed)
(4) Continuity between 13, 26 <M/T> 42, 48 <A/T> and earth
OK: Continuity
(5) Voltage between 80 <M/T>, 66 <A/T> and earth
OK: System voltage
OK
NG
Check the following
connectors:
<M/T> C-34, C-36,
C-40
<A/T> C-175, C-176
OK
Check trouble symptom.
NG
Replace the engine-ECU <M/T> or engine-A/T-ECU <A/T>
MPI <4G6> -
(1) NG
(2), (3) NG
(4) NG
(5) NG
Repair
Troubleshooting
Probable cause
D Improper
short-circuited harness wire in the engine-ECU <M/T>
or engine-A/T-ECU <A/T> power supply circuit.
D Open circuit or short-circuited harness wire in the
engine-ECU <M/T> or engine-A/T-ECU <A/T> earth
circuit
D Malfunction
engine-A/T-ECU <A/T>
Check the following
connectors:
C-92, C-105, C-131
OK
Check trouble symptom.
OK
Check the harness wire
between engine-ECU
<M/T> or engine-
A/T-ECU <A/T> and
ignition switch
connector.
OK
Check the ignition switch.
(Refer to GROUP 54 - Ignition Switch.)
Check the harness wire between engine-ECU <M/T> or engine-
A/T-ECU <A/T> and engine control relay connector, and repair
if necessary.
Check the harness wire between engine-ECU <M/T> or engine-
A/T-ECU <A/T> and earth, and repair if necessary.
Check the following
connectors:
LHD: C-48, C-63, C-66,
C-83, C-132, C-141
RHD: C-14, C-62, C-66,
C-83
OK
Check trouble symptom.
NG
Check the harness wire between engine-ECU <M/T> or
engine-A/T-ECU <A/T> and battery, and repair if necessary.
connector contact, open circuit
of the engine-ECU <M/T>
NG
Repair
NG
Repair
NG
Repair
or
or