Mitsubishi 380. Manual — part 547

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

MULTIPORT FUEL INJECTION (MFI)

13A-280

DTC P0202: Injector Circuit Malfunction - Cylinder 2.

.

CIRCUIT OPERATION

• Refer to DTC P0300 - Random/Multiple Misfire-

P.13A-330

and Misfire Cylinder 2-

P.13A-336

.

• 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

P.13A-11

.

.

AK303102

CONNECTOR: B-30

B-30 (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

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

MULTIPORT FUEL INJECTION (MFI)

13A-281

TROUBLESHOOTING HINTS (The most
likely causes for this code to be set are:)

• No. 2 cylinder injector failed.

• Open or shorted to ground No.2 cylinder injector

circuit.

• Shorted to battery, No.2 cylinder injector circuit.

• Harness or connector damage.

• Refer to component locations GROUP-

70

• Refer to configuration diagrams GROUP-

80

• Refer to circuit diagrams GROUP-

90

DIAGNOSIS

Required Special Tools:

• Diagnostic Tool (MUT-III Sub Assembly)

• MB991824: V.C.I.

• MB991827: USB Cable

• MB991910: Main Harness A

• MB991658: Test Harness
• MB992044: Power Plant ECU Check Harness

STEP 1. Using diagnostic tool , check actuator test item
02: No. 2 injector.

CAUTION

To prevent damage to diagnostic tool , always turn the
ignition switch to the "LOCK" (OFF) position before con-
necting or disconnecting diagnostic tool .
(1) Connect diagnostic tool to the data link connector.
(2) Start the engine and run at idle.
(3) Set diagnostic tool to the actuator testing mode for item 02,

No. 2 injector.

(4) Warm up the engine to normal operating temperature: 80

°C

to 95

°C (176°F to 203°F).

• The idle should become slightly rougher.

(5) Turn the ignition switch to the "LOCK" (OFF) position.

Q: Does the idle vary or engine run "rough"?

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 : Go to Step 2.

STEP 2. Check the harness connector B-30 at No. 2
cylinder injector for damage.
Q: Is the harness connector in good condition?

YES : Go to Step 3.
NO : Repair or replace it. Refer to GROUP 00E, Harness

Connector Inspection

P.00E-2

. Then go to Step 10.

00DB076A

MB991910

DATA LINK

CONNECTOR

MB991824

MB991827

AK303103

M

1

2

CONNECTOR: B-30

B-30 (GR)

HARNESS CONNECTOR:

COMPONENT SIDE

AB

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

MULTIPORT FUEL INJECTION (MFI)

13A-282

STEP 3. Check the No. 2 cylinder injector.
(1) Disconnect the No. 2 cylinder injector connector B-30.

(2) Measure the resistance between injector side connector

terminal No. 1 and No. 2.

Standard value: 10.5

− 13.5 ohms [at 20°C (68°F)]

Q: Is the measured resistance between 10.5 and 13.5 ohms

[at 20

°C (68°F)]?

YES : Go to Step 4.
NO : Replace the No. 2 cylinder injector. Then go to Step

10.

STEP 4. Measure the power supply voltage at No.2 cylinder
injector connector B-30.
(1) Disconnect connector B-30 and measure at the harness

side.

(2) Turn the ignition switch to the "ON" position.

(3) Measure the voltage between terminal No. 1 and ground.

• Voltage should be battery positive voltage.

(4) Turn the ignition switch to the "LOCK" (OFF) position.

Q: Is battery positive voltage (approximately 12 volts)

present?
YES : Go to Step 6.
NO : Go to Step 5.

AK303103

M

1

2

CONNECTOR: B-30

B-30 (GR)

HARNESS CONNECTOR:

COMPONENT SIDE

AB

AK000559

2

1

INJECTOR SIDE
CONNECTOR

AB

AK303103

M

1

2

CONNECTOR: B-30

B-30 (GR)

HARNESS CONNECTOR:

COMPONENT SIDE

AB

AK303104

1

2

B-30 HARNESS

CONNECTOR:

COMPONENT SIDE

AB

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

MULTIPORT FUEL INJECTION (MFI)

13A-283

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.2 cylinder injector
connector B-30 (terminal No. 1) because of open
circuit or short circuit to ground.

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.

1

2

3

4

AK303017

CONNECTOR: B-17X

FRONT OF VEHICLE

B-17X

AB

HARNESS

CONNECTOR:

COMPONENT SIDE

RELAY BOX