Mitsubishi Galant. Manual — part 181

MULTIPORT FUEL INJECTION(MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <2.4L>

13A-405

STEP 3. Check the circuit at PCM connector C-41.
(1) Disconnect the connectors C-41 and measure at the

harness side.

(2) Turn the ignition switch to the "ON" position.
(3) Measure the voltage between terminal 83 and ground.

•

Voltage should be 1 volt or less when the A/C switch is
"OFF".

•

Voltage should be battery positive voltage when the A/C
switch is "ON".

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

Q: Is the voltage normal?

YES : Replace the PCM. Then confirm that the malfunction

symptom is eliminated.

NO : Refer to GROUP 55, Heating and air conditioning

−

Introduction To Heater, Air Conditioning And
Ventilation Diagnosis (

P.55-4

).

DATA LIST REFERENCE TABLE

M1131008900109

CAUTION

•

When shifting the select lever to D range, the brakes should be applied so that the vehicle does
not move forward.

•

Driving tests always need two persons: one driver and one observer.

NOTE:

*1

: If the idle speed is lower than the standard value on a very cold engine (approximately -20

°

C (-4

°

F) even when the IAC motor is fully opened, the air volume limiter built in the throttle body could be defective.

NOTE:

*2

: In a new vehicle [driven approximately 500 km (311 mile) or less], the step of the stepper motor is

sometimes 30 steps greater than the standard value.

NOTE:

*3

: The injector drive time represents the time when the cranking speed is at 250 r/min or below when

the power supply voltage is 11 volts.

NOTE:

*4

: In a new vehicle [driven approximately 500 km (311 mile) or less], the injector drive time is

sometimes 10% longer than the standard time.

NOTE:

*5

: In a new vehicle [driven approximately 500 km (311 mile) or less], the volume air flow sensor

output frequency is sometimes 10% higher than the standard frequency.

NOTE:

*6

: Applicable to General Scan Tool (GST).

AKX01449

71

72

73

74

75

76

77
89 88 87 86 858483 82 8180 7978

90

91

92

93

94

95

96

97

98

C-41 HARNESS
SIDE CONNECTOR

AE

MUT-II
SCAN
TOOL
DISPLAY

ITEM

NO.

INSPECTION
ITEM

INSPECTION
REQUIREMENT

NORMAL
CONDITION

INSPECTION
PROCEDURE
NO.

REFERENCE
PAGE

A/C
RELAY

49

A/C
compressor
clutch relay

Engine:
warming up,
idling

A/C switch:
"OFF"

OFF
(Compressor
clutch is not
operating)

Procedure
No.33

P.13A-
403

A/C switch:
"ON"

ON
(Compressor
clutch is
operating)

MULTIPORT FUEL INJECTION(MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <2.4L>

13A-406

A/C
SWITCH

28

A/C switch

Engine: idle
(when A/C
switch is ON,
A/C
compressor
should be
operating)

A/C
switch:"OFF"

OFF

Procedure
No.33

P.13A-
403

A/C
switch:"ON"

ON

BARO
SENSOR

25

Barometric
pressure
sensor

Ignition switch:
"ON"

At altitude of
0 m (0 ft)

101 kPa

Code
No.P0107,P0
108

P.13A-
41

,

P.13A

-50

At altitude of
600 m (1,969
ft)

95 kPa

At altitude of
1,200 m
(3,937 ft)

88 kPa

At altitude of
1,800 m
(5,906 ft)

81 kPa

BATT
VOLTAGE

16power supply

voltage

Ignition switch: "ON"

Battery positive
voltage

Procedure
No.29

P.13A-
379

MUT-II
SCAN
TOOL
DISPLAY

ITEM

NO.

INSPECTION
ITEM

INSPECTION
REQUIREMENT

NORMAL
CONDITION

INSPECTION
PROCEDURE
NO.

REFERENCE
PAGE

MULTIPORT FUEL INJECTION(MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <2.4L>

13A-407

CRANK
SENSOR

22

Crankshaft
position sensor

*1

•

Engine: cranking

•

Tachometer: connected

Engine speeds
displayed on
the scan tool
and
tachometer are
identical.

Code
No.P0335

P.13A-
170

Engine: idling

Engine
coolant
temperature
is -20

°

C (-

40

°

F)

1,275

−

1,475

r/min

Engine
coolant
temperature
is 0

°

C (32

°

F)

1,220

−

1,420

r/min

Engine
coolant
temperature
is 20

°

C (68

°

F)

1,100

−

1,300

r/min

Engine
coolant
temperature
is 40

°

C

(104

°

F)

930

−

1,130 r/

min

Engine
coolant
temperature
is 80

°

C

(176

°

F)

600

−

800 r/

min

CRANK.
SIGNAL

18

Cranking
signal (ignition
switch-ST)

Ignition switch:
"ON"

Engine:
stopped

OFF

Procedure
No.31

P.13A-
392

Engine:
cranking

ON

MUT-II
SCAN
TOOL
DISPLAY

ITEM

NO.

INSPECTION
ITEM

INSPECTION
REQUIREMENT

NORMAL
CONDITION

INSPECTION
PROCEDURE
NO.

REFERENCE
PAGE

MULTIPORT FUEL INJECTION(MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <2.4L>

13A-408

ECT
SENSOR

21

Engine coolant
temperature
sensor

Ignition switch:
"ON"or with
engine running

Engine
coolant
temperature
is -20

°

C (-4

°

F)

-20

°

C (-4

°

F)

Code
No.P0115,P0
116,P0117

P.13A-
66

,

P.13A

-
74

,

P.13A

-79

Engine
coolant
temperature
is 0

°

C (32

°

F)

0

°

C(32

°

F)

Engine
coolant
temperature
is 20

°

C (68

°

F)

20

°

C(68

°

F)

Engine
coolant
temperature
is 40

°

C(104

°

F)

40

°

C (104

°

F)

Engine
coolant
temperature
is 80

°

C

(176

°

F)

80

°

C (176

°

F)

HO2S
BANK1
S1

11

Heated oxygen
sensor (front)

Engine:
Warming up
(air/fuel
mixture is
made leaner
when
decelerating,
and is made
richer when
revving.)

When at
4000 r/min,
engine is
suddenly
decelerated

200 mV or less

→

600

−

1,000

mV (After
several
seconds have
elapsed)

Code
No.P0130,P0
133,P0134

P.13A-
105

,

P.13

A-
113

,

P.13

A-115

Engine:
Warming up
(the heated
oxygen sensor
signal is used
to check the
air/fuel mixture
ratio, and
control
condition is
also checked
by the PCM)

Engine is
idling

Voltage
changes
repeatedly
between 400
mV or less and
600

−

1,000

mV.

2,500 r/min

MUT-II
SCAN
TOOL
DISPLAY

ITEM

NO.

INSPECTION
ITEM

INSPECTION
REQUIREMENT

NORMAL
CONDITION

INSPECTION
PROCEDURE
NO.

REFERENCE
PAGE