Mitsubishi Galant. Manual — part 123

MULTIPORT FUEL INJECTION(MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <2.4L>

13A-173

STEP 3. Check connector B-20 at the crankshaft position
sensor for damage.
Q: Is the connector in good condition?

YES : Go to Step 4.
NO : Repair or replace it. Refer to GROUP 00E, Harness

Connector Inspection (

P.00E-2

). Then go to Step 20.

STEP 4. Using scan tool MB991502, check data list item 22:
Crankshaft Position Sensor.

CAUTION

To prevent damage to scan tool MB991502, always turn the
ignition switch to the "LOCK"(OFF) position before
connecting or disconnecting scan tool MB991502.
(1) Connect scan tool MB991502 to the data link connector.
(2) Turn the ignition switch to the "ON" position.
(3) Set scan tool MB991502 to the data reading mode for item

22, Crankshaft Position Sensor.

•

The tachometer and engine speed indicated on the scan
tool should much.

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

Q: Is the sensor operating properly?

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

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

P.00-8

).

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

STEP 5. Check connector B-20 at the crankshaft position
sensor for damage.
Q: Is the connector in good condition?

YES : Go to Step 6.
NO : Repair or replace it. Refer to GROUP 00E, Harness

Connector Inspection (

P.00E-2

). Then go to Step 20.

AK000562AB

CONNECTOR:B-20

AC003081 AB

16 PIN

MB991502

AK000562AB

CONNECTOR:B-20

MULTIPORT FUEL INJECTION(MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <2.4L>

13A-174

STEP 6. Check the sensor supply voltage at crankshaft
position sensor harness side connector B-20.
(1) Disconnect the connector B-20 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 11.
NO : Go to Step 7.

STEP 7. Check the sensor supply voltage at PCM
connector C-40 by backprobing
(1) Do not disconnect the PCM connector C-40.
(2) Disconnect the crankshaft position sensor connector B-20.
(3) Turn the ignition switch to the "ON" position.
(4) Measure the voltage between terminal 45 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 8.
NO : Go to Step 9.

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

YES : Repair it because of open circuit between crankshaft

position sensor connector B-20 terminal 2 and PCM
connector C-40 terminal 45. Then go to Step 20.

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

Connector Inspection (

P.00E-2

). Then go to Step 20.

STEP 9. Check connector C-40 at PCM for damage.
Q: Is the connector in good condition?

YES : Go to Step 10.
NO : Repair or replace it. Refer to GROUP 00E, Harness

Connector Inspection (

P.00E-2

). Then go to Step 20.

AKX01416 AC

2 1

3

B-20 HARNESS
SIDE CONNECTOR

AK000297

C-40 CONNECTOR
HARNESS SIDE VIEW

41
47
58

42
48

43
49

59

44
55

64

45
56

65

46
57

66

50
60

51
61

52
62

53 54
63

AC

AK000280

CONNECTOR : C-40

PCM

AV

AK000280

CONNECTOR : C-40

PCM

AV

MULTIPORT FUEL INJECTION(MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <2.4L>

13A-175

STEP 10. Check for short circuit to ground between
crankshaft position sensor connector B-20 terminal 2 and
PCM connector C-40 terminal 45.
Q: Is the harness wire in good condition?

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

STEP 11. Check the power supply voltage at crankshaft
position sensor harness side connector B-20.
(1) Disconnect the connector B-20 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 13.
NO : Go to Step 12.

STEP 12. 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 crankshaft position sensor
connector B-20 terminal 3 because of open circuit or
short circuit to ground. Then go to Step 20.

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

Connector Inspection (

P.00E-2

). Then go to Step 20.

AK000562AB

CONNECTOR:B-20

AK000280

CONNECTOR : C-40

PCM

AV

AKX01417AC

2 1

3

B-20 HARNESS
SIDE CONNECTOR

AK000555AB

CONNECTOR : A-21X

MFI RELAY

MULTIPORT FUEL INJECTION(MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <2.4L>

13A-176

STEP 13. Check the continuity at crankshaft position
sensor harness side connector B-20.
(1) Disconnect the connector B-20 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 14.
NO : Repair harness wire between crankshaft position

sensor connector B-20 terminal 1 and ground
because of open circuit or harness damage. Then go
to Step 20.

STEP 14. Check connector A-21X at the MFI relay for
damage.
Q: Is the harness connector in good condition?

YES : Go to Step 15.
NO : Repair or replace it. Refer to GROUP 00E, Harness

Connector Inspection (

P.00E-2

). Then go to Step 20.

STEP 15. Check connector C-40 at PCM for damage.
Q: Is the connector in good condition?

YES : Go to Step 16.
NO : Repair or replace it. Refer to GROUP 00E, Harness

Connector Inspection (

P.00E-2

). Then go to Step 20.

AKX01418 AC

2 1

3

B-20 HARNESS
SIDE CONNECTOR

AK000555AB

CONNECTOR : A-21X

MFI RELAY

AK000280

CONNECTOR : C-40

PCM

AV