Mitsubishi Galant 9G. Manual — part 1082

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.8L ENGINE>

13B-628

DTC SET CONDITIONS <Range/Performance problem - Alignment>

Logic Flow Chart

.

DTC SET CONDITIONS

Check Conditions

• Engine speed is higher than 50 r/min.

Judgment Criteria

• Normal signal pattern has not been input for cyl-

inder identification from the crankshaft position
sensor signal and camshaft position sensor sig-
nal for 2 seconds.

.

START

END

YES

NO

NO

YES

MALFUNCTION

GOOD

CONTINUOUS

FAILURE FOR 2secs

EXPECTED STATE

OF THE SENSOR

MONITORING
CONDITIONS?

YES

NO

AK302393

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.8L ENGINE>

13B-629

DTC SET CONDITIONS <Range/Performance problem - Circuit continuity>

Logic Flow Chart

.

Check Conditions

• Engine speed is higher than 50 r/min.

Judgment Criteria

• Camshaft position sensor output voltage has not

changed (no pulse signal is input) for 2 seconds.

.

OBD-II DRIVE CYCLE PATTERN

Refer to Diagnostic Function

− OBD-II Drive Cycle −

Procedure 6

− Other Monitor

P.13B-6

.

.

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

• Camshaft position sensor failed.

• Open or shorted camshaft position sensor circuit,

or harness damage, or connector damage.

• PCM failed.

START

END

NO

NO

YES

YES

MALFUNCTION

GOOD

OUTPUT SIGNAL

CHANGES

CONTINUOUS

FAILURE FOR 2secs

MONITORING

CONDITIONS?

YES

NO

AK302394

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.8L ENGINE>

13B-630

DIAGNOSIS

Required Special Tools:

• MB991709: Test Harness Set

• MB991923: Power Plant ECU Check Harness

STEP 1. Using the oscilloscope, check the camshaft
position sensor.
(1) Disconnect the camshaft position sensor connector B-106,

and connect test harness special tool (MB991709) between
the separated connectors (All terminals should be
connected).

(2) Connect the oscilloscope probe to the camshaft position

sensor 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 connector the osilloscope probe to the
check harness connector terminal No. 104.

(3) Start the engine and run at idle.

(4) Check the waveform.

• The waveform should show a pattern similar to the illus-

tration.

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

YES : Go to Step 2..
NO : Go to Step 4.

STEP 2. Check harness connector B-106 at camshaft
position sensor 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 20.

1

2

3

AK303130

HARNESS
CONNECTOR:
COMPONENT SIDE

AB

CAMSHAFT POSITION
SENSOR

B-106 (B)

CONNECTOR: B-106

AK102976AB

1 2 3

CAMSHAFT POSITION
SENSOR CONNECTOR

OSCILLOSCOPE

MB991709

AK302213AB

2 ENGINE REVOLUTIONS

NORMAL WAVEFORM

5V

1

2

3

AK303130

HARNESS
CONNECTOR:
COMPONENT SIDE

AB

CAMSHAFT POSITION
SENSOR

B-106 (B)

CONNECTOR: B-106

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.8L ENGINE>

13B-631

STEP 3. Check the trouble symptoms.
(1) Carry out a test drive with the drive cycle pattern. Refer to

Diagnostic Function

− OBD-II Drive Cycle − Procedure 6 −

Other Monitor

P.13B-6

.

(2) Check the diagnostic trouble code (DTC).
Q: Is DTC P0340 set?

YES : Replace the PCM. Then go to Step 20.
NO : 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

.

STEP 4. Check harness connector B-106 at camshaft
position sensor for damage.
Q: Is the harness connector in good condition?

YES : Go to Step 5.
NO : Repair or replace it. Refer to GROUP 00E, Harness

Connector Inspection

P.00E-2

. Then go to Step 20.

STEP 5. Measure the sensor supply voltage at camshaft
position sensor connector B-106.
(1) Disconnect the connector B-106 and measure at the

harness side.

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

(3) Measure the voltage between terminal No. 2 and ground.

• Voltage should be between 4.9 and 5.1 volts.

(4) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the measured voltage between 4.9 and 5.1 volts?

YES : Go to Step 10.
NO : Go to Step 6.

1

2

3

AK303130

HARNESS
CONNECTOR:
COMPONENT SIDE

AB

CAMSHAFT POSITION
SENSOR

B-106 (B)

CONNECTOR: B-106

1

2

3

AK303130

HARNESS
CONNECTOR:
COMPONENT SIDE

AB

CAMSHAFT POSITION
SENSOR

B-106 (B)

CONNECTOR: B-106

AKX01421AF

B-106 HARNESS
CONNECTOR:
COMPONENT SIDE

3 2 1