Mitsubishi 380. Manual — part 550
MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS
MULTIPORT FUEL INJECTION (MFI)
13A-292
STEP 8. Check for harness damage between MFI relay
connector B-17X (terminal No. 4) and intermediate
connector B-32 (terminal No. 9).
Q: Is the harness wire in good condition?
YES : Go to Step 9.
NO : Repair it. Then go to Step 12.
1
2
3
4
AK303017
CONNECTOR: B-17X
FRONT OF VEHICLE
B-17X
AB
HARNESS
CONNECTOR:
COMPONENT SIDE
RELAY BOX
AK303053
3
4
5
8
9
1
2
6
7
10
CONNECTOR: B-32
HARNESS CONNECTOR:
COMPONENT SIDE
AB
B-32 (B)
MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS
MULTIPORT FUEL INJECTION (MFI)
13A-293
STEP 9. Check harness connector B-20 at ECU for
damage.
Q: Is the harness connector in good condition?
YES : Go to Step 10.
NO : Repair or replace it. Refer to GROUP 00E, Harness
Connector Inspection
. Then go to Step 12.
STEP 10. Check for open circuit and short circuit to
ground and harness damage between intermediate
connector B-32 (terminal No. 10) and ECU connector B-20
(terminal No. 34).
Q: Is the harness wire in good condition?
YES : Go to Step 11.
NO : Repair it. Then go to Step 12.
16DB400A
COVER
ENGINE
CONTROL
UNIT
AIR
CLEANER
AK303053
3
4
5
8
9
1
2
6
7
10
CONNECTOR: B-32
HARNESS CONNECTOR:
COMPONENT SIDE
AB
B-32 (B)
16DB400A
COVER
ENGINE
CONTROL
UNIT
AIR
CLEANER
MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS
MULTIPORT FUEL INJECTION (MFI)
13A-294
STEP 11. Using the oscilloscope, check the No. 3 cylinder
injector.
(1) Disconnect the intermediate connector B-32 and connect
the test harness MB991658 between the separated
connectors.
(2) Connect the oscilloscope probe to injector intermediate
connector terminal No. 10.
NOTE: When measuring with the ECU side connector, dis-
connect the all ECU connectors and connect check harness
special tool (MB992044) between the separated connec-
tors. Then connect an oscilloscope probe to the check har-
ness connector terminal No. 34.
(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 00E, How to Use Troubleshooting/Inspection
Service Points
− How to Cope with Intermittent
Malfunctions
.
NO : Replace the ECU. Then go to Step 12.
STEP 12. Test the EOBD drive cycle.
(1) Carry out a test drive with the drive cycle pattern. Refer to
Diagnostic Function
− EOBD Drive Cycle −
(2) Check the diagnostic trouble code (DTC).
Q: Is DTC P0203 set?
YES : Retry the troubleshooting.
NO : The inspection is complete.
AK303053
3
4
5
8
9
1
2
6
7
10
CONNECTOR: B-32
HARNESS CONNECTOR:
COMPONENT SIDE
AB
B-32 (B)
1 2 3
6 7 8
4 5
9 10
AK203300
OSCILLOSCOPE
MB991658
B-32 INTERMEDIATE
CONNECTOR
AB
AKX01557 AB
A
NORMAL WAVEFORM
A:INJECTOR DRIVE TIME
MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS
MULTIPORT FUEL INJECTION (MFI)
13A-295
DTC P0204: Injector Circuit Malfunction - Cylinder 4.
.
CIRCUIT OPERATION
• Refer to DTC P0300 - Random/Multiple Misfire-
and Misfire Cylinder 4-
.
• The injector power is supplied from the MPI relay
(terminal No. 4).
• The ECU controls the injector by turning the
power transistor in the ECU "ON" and "OFF".
.
TECHNICAL DESCRIPTION
• The amount of fuel injected by the injector is con-
trolled by the amount of continuity time the coil is
grounded by the ECU.
• A surge voltage is generated when the injectors
are switched on/off.
• The ECU monitors this surge voltage.
.
DTC SET CONDITIONS <Circuit continuity
− open circuit and shorted low>
Check Conditions
• Battery voltage is between 9.04 and 16.01vols.
• Engine speed is above 801 r/min.
Judgment Criteria
• IC internal test (open circuit, short to earth, short
to battery).
• MIL on after 2 drive cycles.
• Misfire present.
.
EOBD DRIVE CYCLE PATTERN
Refer to Diagnostic Function
− EOBD Drive Cycle −
.
.
AK303109
CONNECTOR: B-27
B-27 (GR)
AB
1
2
3
4
1
2
3
4
1
2
3
4
1
2
3
4
AK303014
CONNECTOR: B-17X
MFI RELAY
MFI RELAY
FRONT OF VEHICLE
B-17X
AB
16DB400A
COVER
ENGINE
CONTROL
UNIT
AIR
CLEANER
Нет комментариевНе стесняйтесь поделиться с нами вашим ценным мнением.
Текст