Mitsubishi Montero Sport (2004+). Manual — part 155

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-33

DIAGNOSTIC TROUBLE CODE PROCEDURES

DTC P0101: Volume Airflow Circuit Range / Performance Problem

WHITE-

BL

ACK

WHITE-

BL

ACK

RED

RED

RED

BL

ACK

BL

ACK

GREEN-BL

UE

WHITE-BL

ACK

WHITE-

BL

ACK

1 2 3 4 5 6 7

1

10

2 3 4 5 6 7 8 9

11

12 13 14 15 16 17 18 19 20 21 22

23 24 25 26 27 28 29 30 31 32 33

47

41

42 43

48 49 50 51 52 53 54 55 56 57

46

45

44

58

59

60 61 62 63

64 65 66

10

2

3 4

5 6

7 8

9

11 12 13 14 15 16 17 18 19 20

30

21 22 23

24

25

26 27 28 29

31 32 33

34 35

1

AK301854

Volume Airflow Sensor Circuit

C-71

FUSIBLE LINK(12)

MFI RELAY

VOLUME
AIRFLOW
SENSOR

65

3

57

19

4

24

12

4

3

5

7

12

33

22

2

1

15

C-90
(MU803781)

C-89
(MU803784)

POWERTRAIN CONTROL MODULE (PCM)

A-01

C-59

5V

1

10

2 3 4 5 6 7 8 9

11

12 13 14 15 16 17 18 19 20 21 22

23 24 25 26 27 28 29 30 31 32 33

C-14

JOINT
CONNECTOR (5)

JOINT
CONNEC-
TOR (4)

1

2

3

4

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-34

.

CIRCUIT OPERATION

• The volume airflow sensor power is supplied from

the MFI relay (terminal No. 1), and the ground is
provided on the PCM (terminal No. 57).

• 5-volt power is applied to the volume airflow sen-

sor output terminal (terminal No. 3) from the PCM
(terminal No. 65). The volume airflow sensor gen-
erates a pulse signal when the output terminal
and ground are opened/closed (opened/short).

• 6-9volts power is applied to the PCM (terminal

No.19) from the volume airflow sensor (terminal
No.7).

• The PCM (terminal No.19) controls the airflow

sensor reset signal by turning the power transis-
tor within the PCM to "ON" and "OFF" position.

.

TECHNICAL DESCRIPTION

• While the engine is running, the volume airflow

sensor outputs a pulse signal which corresponds
to the volume of air flow.

• The PCM checks whether the frequency of this

signal output by the volume airflow sensor while
the engine is running is at or above the set value.

• When the throttle position sensor output voltage

is low, the PCM causes the power transistor to be
"ON" to send an volume airflow sensor reset sig-
nal to the volume airflow sensor. In response to
the reset signal, the volume airflow sensor resets
the filter circuit and improves the ability of the air-
flow sensor to measure the amount of air in a
small air intake region.

.

DESCRIPTIONS OF MONITOR METHODS
Compare load value with volume airflow sensor out-

put frequency.

.

MONITOR EXECUTION
Continuous

.

AK103908

CONNECTOR: A-01

VOLUME
AIRFLOW
SENSOR

A-01(B)

AE

AK201000

MFI RELAY

CONNECTOR: C-59

AB

C-59

AK103738AB

CONNECTORS: C-89, C-90

PCM

C-89(GR) C-90(GR)

AK103911AB

CONNECTOR: C-14

C-14

AK103912AB

CONNECTOR: C-71

C-71

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-35

MONITOR EXECUTION CONDITIONS (Other
monitor and Sensor)

Other Monitor (There is no temporary DTC stored

in memory for the item monitored below)

• Not applicable

Sensor (The sensor below is determined to be

normal)

• Throttle position sensor

.

DTC SET CONDITIONS<Range/Performance-low input>

Logic Flow Chart

Check Conditions

• Throttle position sensor output voltage is 1.5 volts

or higher.

• Engine speed is higher than 2,000 r/min.

Judgement Criteria

• Volume airflow sensor output frequency has con-

tinued to be 60 Hz or lower for 2 seconds.

.

START

MONITORING

CONDITIONS

END

NO

YES

NO

YES

NO

YES

MALFUNCTION

GOOD

OUTPUT FREQUENCY

< =60Hz

CONTINUOUS

FAILURE FOR 2 secs

AK301412

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-36

DTC SET CONDITIONS<Range/Performance-high input>

Logic Flow Chart

.

Check Conditions

• Throttle position sensor voltage is 2 volts or

lower.

• Engine speed is lower than 2,000 r/min.

Judgement Criteria

• Volume airflow sensor output frequency has con-

tinued to be 800 Hz or higher for 2 seconds.

.

OBD-II DRIVE CYCLE PATTERN
Refer to Diagnostic Function

− OBD-II Drive Cycle −

Procedure 6

− Other Monitor

P.13A-4

.

.

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

• Volume airflow sensor failed.

• Open or shorted volume airflow sensor circuit,

harness damage or connector damage.

• PCM failed.

DIAGNOSIS

Required Special Tools:

• MB991958: Scan Tool (MUT-III Sub Assembly)

• MB991824: V.C.I.

• MB991827: USB Cable

• MB991911: Main Harness B

START

MONITORING

CONDITIONS

END

NO

YES

NO

YES

NO

YES

MALFUNCTION

GOOD

OUTPUT FREQUENCY

> =800Hz

CONTINUOUS

FAILURE FOR 2 secs

AK301411