Mitsubishi Eclipse. Manual - part 144

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <2.4L>

13A-69

CIRCUIT OPERATION

• A 5-volt voltage is supplied to the manifold abso-

lute pressure sensor power terminal (terminal No.
3) from the ECM (terminal No. 81) or PCM (termi-
nal No. 46) <A/T>. The ground terminal (terminal
No. 2) is grounded with the ECM (terminal No.
92) <M/T> or PCM (terminal No. 57) <A/T>.

• A voltage that is proportional to the intake mani-

fold pressure is sent to the ECM (terminal No. 73)
<M/T> or PCM (terminal No. 91) <A/T> from the
manifold absolute pressure sensor output termi-
nal (terminal No. 1).

TECHNICAL DESCRIPTION

• The manifold absolute pressure sensor outputs a

voltage which corresponds to the intake manifold
pressure.

• The ECM <M/T> or PCM <A/T> checks whether

this voltage is within a specified range.

DESCRIPTIONS OF MONITOR METHODS
Manifold absolute pressure sensor output voltage is

out of specified range.

MONITOR EXECUTION
Continuous

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)

• Engine coolant temperature sensor

• Throttle position sensor

AK300106AB

CONNECTOR: B-04

B-04 (B)

MANIFOLD
ABSOLUTE
PRESSURE
SENSOR

AK300060

ECM

CONNECTOR: C-60 <M/T>

C-60 (G)

AK300060

PCM

CONNECTORS: C-54, C-57 <A/T>

C-57 (GR)

C-54 (GR)

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <2.4L>

13A-70

DTC SET CONDITIONS

Logic Flow Chart

Check conditions

Check Conditions

• 8 minutes or more have passed since the starting

sequence was completed, when the engine cool-
ant temperature at engine start is 0

°C (32°F) or

lower.

• Throttle position sensor output voltage is higher

than 1.25 volts.

Judgement Criteria

• Manifold Absolute pressure is 4.9 kPa (1.4 in.Hg)

or lower for 2 seconds.

OBD-ll DRIVE CYCLE PATTERN
Refer to Diagnostic Function

− OBD-ll Drive Cycle −

Procedure 6

− Other Monitor

P.13A-5

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

• Manifold absolute pressure sensor failed.

• Open or shorted manifold absolute pressure sen-

sor circuit, harness damage or connector dam-
age.

• ECM failed <M/T>.

• PCM failed <A/T>.

YES

MONITORING

CONDITIONS

PRESSURE < 4.9kPa (1.4in.Hg)

PRESSURE > 117kPa (34.6in.Hg)

CONTINUOUS

FAILURE FOR 2secs

MALFUNCTION

END

GOOD

START

AK301416

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <2.4L>

13A-71

DIAGNOSIS

Required Special Tools:

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

• MB991824: V.C.I.

• MB991827: USB Cable

• MB991911: Main Harness B

STEP 1. Using scan tool MB991958, check data list item 95:
Manifold Absolute Pressure Sensor.

CAUTION

To prevent damage to scan tool MB991958, always turn the
ignition switch to the "LOCK" (OFF) position before con-
necting or disconnecting scan tool MB991958.
(1) Connect scan tool MB991958 to the data link connector.
(2) Turn the ignition switch to the "ON" position.
(3) Set scan tool MB991958 to the data reading mode for item

95, Manifold Absolute Pressure Sensor.

• When altitude is 0 m (0 foot), 101 kPa (29.8 in.Hg).

• When altitude is 600 m (1,969 feet), 95 kPa (28.1 in.Hg).

• When altitude is 1,200 m (3,937 feet), 88 kPa (26.0

in.Hg).

• When altitude is 1,800 m (5,906 feet), 81 kPa (23.9

in.Hg).

(4) Start the engine.

• When the engine is idling, 16 − 36 kPa (4.7 − 10.6

in.Hg).

• When the engine is suddenly revved, manifold absolute

pressure increases.

(5) 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.00-6

NO : Go to Step 2.

AK300810

MB991911

16-PIN

MB991827

MB991824

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <2.4L>

13A-72

STEP 2. Measure the sensor output voltage at Manifold
absolute pressure sensor connector B-04 by backprobing.
(1) Do not disconnect the connector B-04.
(2) Turn the ignition switch to the "ON" position.

(3) Measure the voltage between terminal No. 1 and ground by

backprobing.

• When altitude is 0 m (0 foot), voltage should be 3.8 and

4.2 volts.

• When altitude is 600 m (1,969 feet), voltage should be

3.5 and 3.9 volts.

• When altitude is 1,200 m (3,937 feet), voltage should be

3.3 and 3.7 volts.

• When altitude is 1,800 m (5,906 feet), voltage should be

3.0 and 3.4 volts.

(4) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the voltage normal?

YES : Go to Step 3.
NO : Go to Step 7.

AK300107

CONNECTOR: B-04

B-04 (B)

HARNESS CONNECTOR:
COMPONENT SIDE

AK203034

B-04 HARNESS
CONNECTOR:
HARNESS SIDE

Content .. 142 143 144 145 ..