Mitsubishi Galant 9G. Manual — part 757

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <2.4L ENGINE>

13A-470

STEP 5. Check harness connector B-17X at MFI relay for
damage.
Q: Is the harness connector in good condition?

YES : Repair harness wire between MFI relay connector

B-17X (terminal No. 4) and No. 1 cylinder injector
connector B-01 (terminal No. 1). Then go to Step
10.

NO : Repair or replace it. Refer to GROUP 00E, Harness

Connector Inspection

P.00E-2

. Then go to Step 10.

STEP 6. Check for harness damage between MFI relay
connector B-17X (terminal No. 4) and No. 1 cylinder
injector connector B-01 (terminal No. 1).
Q: Is the harness wire in good condition?

YES : Go to Step 7.
NO : Repair it. Then go to Step 10.

AK303806

2

1

3

4

AB

CONNECTOR: B-17X

B-17X

RELAY BOX
TRIANGLE
MARK

HARNESS CONNECTOR:
COMPONENT SIDE

AK303806

2

1

3

4

AB

CONNECTOR: B-17X

B-17X

RELAY BOX
TRIANGLE
MARK

HARNESS CONNECTOR:
COMPONENT SIDE

M

1

2

AK303843

B-01 (GR)

CONNECTOR: B-01

AB

HARNESS CONNECTOR:
COMPONENT SIDE

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <2.4L ENGINE>

13A-471

STEP 7. Check harness connector B-23 at PCM for
damage.
Q: Is the harness connector in good condition?

YES : Go to Step 8.
NO : Repair or replace it. Refer to GROUP 00E, Harness

Connector Inspection

P.00E-2

. Then go to Step 10.

127 126 125 124 123 122 121

133 132 131 130 129 128

140 139 138 137 136 135 134

146 145 144 143 142 141

153 152 151 150 149 148 147

AK303058

HARNESS CONNECTOR:
COMPONENT SIDE

CONNECTOR: B-23

B-23

PCM

AB

AIR CLEANER

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <2.4L ENGINE>

13A-472

STEP 8. Check for open circuit and short circuit to ground
and harness damage between No. 1 cylinder injector
connector B-01 (terminal No. 2) and PCM connector B-23
(terminal No. 153).
Q: Is the harness wire in good condition?

YES : Go to Step 9.
NO : Repair it. Then go to Step 10.

M

1

2

AK303843

B-01 (GR)

CONNECTOR: B-01

AB

HARNESS CONNECTOR:
COMPONENT SIDE

127 126 125 124 123 122 121

133 132 131 130 129 128

140 139 138 137 136 135 134

146 145 144 143 142 141

153 152 151 150 149 148 147

AK303058

HARNESS CONNECTOR:
COMPONENT SIDE

CONNECTOR: B-23

B-23

PCM

AB

AIR CLEANER

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <2.4L ENGINE>

13A-473

STEP 9. Using the oscilloscope, check the No. 1 cylinder
injector.
(1) Disconnect the No. 1 cylinder injector connector B-01 and

connect the test harness special tool MB991658 between
the separated connectors. (All terminals should be
connected.)

(2) Connect the oscilloscope probe to the injector side

connector terminal No. 2.
NOTE: When measuring with the PCM side connector, dis-
connect the all PCM connectors and connect check har-
ness special tool (MB991923) between the separated
connectors. Then connect the oscilloscope probe to the
check harness connector terminal No. 153.

(3) Start the engine and run at idle.

(4) Measure the waveform.

• The waveform should show a normal pattern similar to

the illustration.

(5) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the waveform normal?

YES : It can be assumed that this malfunction is intermittent.

Refer to GROUP 00, How to Use
Troubleshooting/Inspection Service Points

− How to

Cope with Intermittent Malfunctions

P.00-14

.

NO : Replace the PCM. Then go to Step 10.

STEP 10. Test the OBD-II drive cycle.
(1) Carry out a test drive with the drive cycle pattern. Refer to

Diagnostic Function

− OBD-II Drive Cycle − Procedure 6 −

Other Monitor

P.13A-6

.

(2) Check the diagnostic trouble code (DTC).
Q: Is DTC P0201 set?

YES : Retry the troubleshooting.
NO : The inspection is complete.

M

1

2

AK303843

B-01 (GR)

CONNECTOR: B-01

AB

HARNESS CONNECTOR:
COMPONENT SIDE

AK302166

1 2

INJECTOR
CONNECTOR

MB991658

OSCILLOSCOPE

AB

AKX01557 AB

A

NORMAL WAVEFORM

A:INJECTOR DRIVE TIME