Mitsubishi Galant. Manual - part 125

MULTIPORT FUEL INJECTION(MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <2.4L>

13A-181

DIAGNOSIS

STEP 1. Using the oscilloscope, check the camshaft
position sensor.
(1) Disconnect the camshaft position sensor connector B-12,

and connect test harness special tool (MB991348) in
between. (All terminals should be connected.)

(2) Connect the oscilloscope probe to the camshaft position

sensor side connector terminal 2.

NOTE: When measuring with the PCM side connector,
connect an oscilloscope probe to terminal 56.

(3) Start the engine and run at idle.
(4) Check the waveform.

•

The waveform should show a pattern similar to the
illustration.

(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 connector B-12 at camshaft position
sensor for damage.
Q: Is the 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 18.

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

Procedure 6

−

Other Monitor(

P.13A-5

(2) Check the diagnostic trouble code (DTC).

Q: Is the DTC P0340 is output?

YES : Replace the PCM. Then go to Step 18.
NO : It can be assumed that this malfunction is intermittent.

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

P.00-8

AKX01419 AB

CAMSHAFT POSITION
SENSOR CONNECTOR

1 2 3

OSCILLOSCOPE

OSCILLO-
SCOPE
PROBE

AKX01420AB

2 ENGINE REVOLUTIONS

NORMAL WAVEFORM

AK000563AB

CONNECTOR:B-12

MULTIPORT FUEL INJECTION(MFI) DIAGNOSIS

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MULTIPORT FUEL INJECTION (MFI) <2.4L>

13A-182

STEP 4. Check connector B-12 at camshaft position
sensor for damage.
Q: Is the 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 18.

STEP 5. Check the sensor supply voltage at camshaft
position sensor connector B-12.
(1) Disconnect the connector B-12 and measure at the harness

side.

(2) Turn the ignition switch to the "ON" position.
(3) Measure the voltage between terminal 2 and ground.

•

Voltage should be between 4.8 and 5.2 volts

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

Q: Is the voltage normal?

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

STEP 6. Check the sensor supply voltage at PCM
connector C-40 by backprobing
(1) Do not disconnect the PCM connector C-40.
(2) Disconnect the camshaft position sensor connector B-12.
(3) Turn the ignition switch to the "ON" position.
(4) Measure the voltage between terminal 56 and ground by

backprobing.

•

Voltage should be between 4.8 and 5.2 volts.

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

Q: Is the voltage normal?

YES : Go to Step 7.
NO : Go to Step 8.

AK000563AB

CONNECTOR:B-12

AKX01421

B-12 HARNESS SIDE
CONNECTOR

AK000318

C-40 CONNECTOR
HARNESS SIDE VIEW

46
57
66

45
56

44
55

43
49

42
48
59

41
47
58

53
63

52
62

51
61

50
60

MULTIPORT FUEL INJECTION(MFI) DIAGNOSIS

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MULTIPORT FUEL INJECTION (MFI) <2.4L>

13A-183

STEP 7. Check connector C-40 at PCM for damage.
Q: Is the connector in good condition?

YES : Repair harness wire between camshaft position

sensor connector B-12 terminal 2 and PCM connector
C-40 terminal 56 because of open circuit. Then go to
Step 18.

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

Connector Inspection (

P.00E-2

). Then go to Step 18.

STEP 8. Check connector C-40 at PCM for damage.
Q: Is the connector in good condition?

YES : Go to Step 9.
NO : Repair or replace it. Refer to GROUP 00E, Harness

Connector Inspection (

P.00E-2

). Then go to Step 18.

STEP 9. Check for short circuit to ground between
camshaft position sensor connector B-12 terminal 2 and
PCM connector C-40 terminal 56.
Q: Is the harness wire in good condition?

YES : Replace the PCM. Then go to Step 18.
NO : Repair it. Then go to Step 18.

AK000280

CONNECTOR : C-40

PCM

AK000280

CONNECTOR : C-40

PCM

AK000563AB

CONNECTOR:B-12

AK000280

CONNECTOR : C-40

PCM

MULTIPORT FUEL INJECTION(MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <2.4L>

13A-184

STEP 10. Check the power supply voltage at camshaft
position sensor connector B-12.
(1) Disconnect the connector B-12 and measure at the harness

side.

(2) Turn the ignition switch to the "ON" position.
(3) Measure the voltage between terminal 3 and ground.

•

Voltage should be battery positive voltage.

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

Q: Is the voltage normal?

YES : Go to Step 12.
NO : Go to Step 11.

STEP 11. Check connector A-21X at MFI relay for damage.
Q: Is the connector in good condition?

YES : Repair harness wire between MFI relay connector A-

21X terminal 1 and camshaft position sensor
connector B-12 terminal 3 because of open circuit or
short circuit to ground. Then go to Step 18.

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

Connector Inspection (

P.00E-2

). Then go to Step 18.

STEP 12. Check the continuity at camshaft position sensor
connector B-12.
(1) Disconnect the connector B-12 and measure at the harness

side.

(2) Check for the continuity between terminal 1 and ground.

•

Should be less than 2 ohm.

Q: Is the continuity normal?

YES : Go to Step 13.
NO : Repair harness wire between camshaft position

sensor connector B-12 terminal 1 and ground
because of open circuit or harness damage. Then go
to Step 18.

STEP 13. Check connector A-21X at the MFI relay for
damage.
Q: Is the connector in good condition?

YES : Go to Step 14.
NO : Repair or replace it. Refer to GROUP 00E, Harness

Connector Inspection (

P.00E-2

). Then go to Step 18.

AKX01422

B-12 HARNESS SIDE
CONNECTOR

AK000555AB

CONNECTOR : A-21X

MFI RELAY

AKX01423

B-12 HARNESS SIDE
CONNECTOR

AK000555AB

CONNECTOR : A-21X

MFI RELAY

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