Mitsubishi Galant. Manual — part 82

MULTIPORT FUEL INJECTION(MFI) DIAGNOSIS

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NOTE: *1 : The test fails if test value is less than this value.

NOTE: *2 : The test fails if test value is greater than this value.

NOTE: *3 : When the test result indicates the following, it means the monitoring of PCM is incomplete.

.

•

"Test incomplete." <in case of Scan tool>

•

"00" or "FF" <in case of General scan tool>

NOTE: *4 : In case that the value output by General scan tool is HEX, convert them after decimalized.

DIAGNOSTIC BY DIAGNOSTIC TEST MODE II
(INCREASED SENSITIVITY)

Required Special Tool:
MB991502: Scan Tool (MUT-II)

TEST
ID

MONITORING
ITEM

SIMPLE TECHNICAL
DESCRIPTION

INDICATION OF SCAN
TOOL*3

CONVERSION
COEFFICIENT IN
USING
GENERAL SCAN
TOOL*4

01

Catalyst
monitor

PCM monitors the deterioration of
catalyst at right bank side by the
output frequency ratio between
heated oxygen sensor (front) and
heated oxygen sensor (rear).

Catalyst Frequency
Ratio Bank 1
Test Result and Limit
Value (max.)

×

0.39

03

EGR monitor

PCM monitors the operation of
EGR system by the pressure
difference of intake manifold
between before and after
introduction of EGR using the
manifold differential pressure
sensor.

EGR Monitor Pressure
Value
Test Result and Limit
Value (min.) kPa

×

0.43 kPa

06Evaporation

leak monitor
(Small leak)

PCM monitors the leak of fuel
evaporation gas by the reduction of
vacuum in tank after appointed time
using the fuel tank differential
pressure sensor after making the
fuel tank and the fuel line vacuum.

EVAP Leak Mon. 1mm
Pressure Value
Test Result and Limit
Value (max.) Pa

×

0.065 Pa

07

Evaporation
leak monitor
(Large leak)

PCM monitors the leak of fuel
evaporation gas by the reduction of
vacuum in tank after appointed time
using the fuel tank differential
pressure sensor after making the
fuel tank and the fuel line vacuum.

EVAP Leak Mon. Gross
Pressure Value
Test Result and Limit
Value (max.) Pa

×

0.065 Pa

MULTIPORT FUEL INJECTION(MFI) DIAGNOSIS

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MULTIPORT FUEL INJECTION (MFI) <2.4L>

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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.

NOTE: When mode II is selected with MUT-II, the Service
Engine Soon/Malfunction Indicator Lamp will light when the
powertrain control module (PCM) first detects the trouble (Note
that this is only for emission-related trouble). At the same time,
the relevant diagnostic trouble codes will be registered. In
respect to the comprehensive component electrical faults
(opens/shorts), the time for the diagnostic trouble code to be
registered after the fault occurrence is four seconds

→

one

second. Therefore, the confirmation of the trouble symptom
and the confirmation after completing repairs can be reduced.
To return to the normal mode I after mode II has been selected
once, the ignition switch must be turned "OFF" once or mode I
must be reselected with MUT-II. The diagnostic trouble code,
readiness test status and freeze frame data, etc., will be erased
when mode I is returned to, so record these before returning to
mode I.
1. Connect scan tool MB991502 to the data link connector.

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

3. Change the diagnostic test mode of the engine control

module to DIAGNOSTIC TEST MODE II (INCREASED
SENSITIVITY).

4. Road test the vehicle.

5. Read the diagnostic trouble code and repair the

malfunctioning part.

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

7. Disconnect scan tool MB991502 from the data link

connector.

INSPECTION USING SCAN TOOL MB991502,
DATA LIST AND ACTUATOR TESTING

Required Special Tool:
MB991502: Scan Tool (MUT-II)

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. Carry out inspection by means of the data list and the

actuator test function. If there is an abnormality, check and
repair the chassis harnesses and components. Refer to
Data List Reference Table (

P.13A-405

).

Refer to Actuator Test Reference Table(

P.13A-416

).

4. Re-check using scan tool MB991502 and check to be sure

that the abnormal input and output have returned to normal
because of the repairs.

AC003081 AB

16 PIN

MB991502

AC003081 AB

16 PIN

MB991502

MULTIPORT FUEL INJECTION(MFI) DIAGNOSIS

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5. Erase the diagnostic trouble code(s).

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

7. Disconnect scan tool MB991502 from the data link

connector.

8. Start the engine again and do a test drive to confirm that the

problem is eliminated.

ON-BOARD DIAGNOSTICS

The powertrain control module (PCM) monitors the input/output signals (some signals all the time and others
under specified conditions) of the PCM. When a malfunction continues for a specified time or longer after the
irregular signal is initially monitored, the PCM judges that a malfunction has occurred. After the PCM first
detects a malfunction, a diagnostic trouble code is recorded when the engine is restarted and the same
malfunction is re-detected. However, for items marked with a "*," a diagnostic trouble code is recorded on the
first detection of the malfunction. There are 55 diagnostic items. The diagnostic results can be read out with a
scan tool. Since memorization of the diagnostic trouble codes is backed up directly by the battery, the
diagnostic results are memorized even if the ignition key is turned off. The diagnostic trouble codes will,
however, be erased when the battery terminal or the PCM connector is disconnected. In addition, the
diagnostic trouble code can also be erased by turning the ignition switch to ON and sending the diagnostic
trouble code erase signal from scan tool MUT-II (MB991502) to the PCM.

NOTE: If the sensor connector is disconnected with the ignition switch turned on, the diagnostic trouble code
is memorized. In this case, send the diagnostic trouble code erase signal to the PCM in order to erase the
diagnostic memory. The 51 diagnostic items are all indicated sequentially from the smallest code number.
The PCM records the engine operating condition when the diagnostic trouble code is set. This data is called
"Freeze-frame" date. This data can be read by using the scan tool, and can then be used in simulation tests
for troubleshooting. Data items are as follows:

OBD- II DRIVE CYCLE

All kinds of diagnostic trouble codes (DTCs) can be monitored by carrying out a short drive according to the
following six drive cycle pattern. In other words, doing such a drive regenerates any kind of trouble which
involves illuminating the Service Engine Soon/Malfunction Indicator Lamp and verifies the repair procedure
has eliminated the trouble (the Service Engine Soon/Malfunction Indicator Lamp is no longer illuminated).

CAUTION

Two technicians should always be in the vehicle when carrying out a test drive.

NOTE: Check that the diagnosis trouble code (DTC) is not output before traveling in the drive cycle pattern.
Erase the DTC if it has been output.

DATA

UNIT

Engine coolant temperature

°

C or

°

F

Engine speed

r/min

Vehicle speed

km/h or mph

Long-term fuel compensation (long-term fuel trim)

%

Short-term fuel compensation (short-term fuel trim)

%

Fuel control condition

•

Open loop

•

Closed loop

•

Open loop-drive condition

•

Open loop-DTC set

•

Closed loop-O

2

(rear) failed

Calculation load value

%

Diagnostic trouble code during data recording

-

MULTIPORT FUEL INJECTION(MFI) DIAGNOSIS

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DRIVE CYCLE PATTERN LIST

PROCEDUR
E

MONITOR ITEM

DIAGNOSTIC TROUBLE
CODE (DTC)

1

Evaporative emission control system leak monitor

P0442, P0450,P0451, P0455

2

Fuel trim monitor

P0171,P0172

3

Catalytic converter monitor

P0421

4

Heated oxygen sensor monitor

P0130, P0133,P0136,P0139

5

Exhaust gas recirculation (EGR) system monitor

P0401

6Other monitor

Main components

P0134, P0300, P0301,
P0302, P0303, P0304,
P0506, P0507,P1400

Sensors and switches

P0101,P0102,P0103,
P0107,P0108, P0111,
P0115,P0116,P0117,
P0121,P0122,P0123, P0335,
P0340, P0551

Wire breakage and short
circuit

P0130, P0135, P0136,
P0141, P0201, P0202,
P0203, P0204, P0403,
P0443, P0446, P1500