Mitsubishi Lancer Evolution X. Manual - part 403

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-677

STEP 1. Test the OBD-II drive cycle.

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) Carry out the test drive with the drive cycle pattern. Refer to 

DIagnostic Function − OBD-II Drive Cycle − Pattern 23 

P.13A-9

.

(4) Check the diagnostic trouble code (DTC).
Q: Is DTC P2229 set?

YES : Replace the ECM. When the ECM is replaced, 

register the ID code. Refer to GROUP 42B, ID Code 
Registration Necessity Judgment Table <Vehicles 
with KOS> 

P.42B-11

 or GROUP 42C, ID Codes 

Registration Judgment Table <Vehicles with WCM> 

P.42C-9

. 

NO :  It can be assumed that this malfunction is intermittent. 

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

Cope with Intermittent Malfunctions 

P.00-15

.

DTC P2252: Heated Oxygen Sensor Offset Circuit Low Voltage 

.

TECHNICAL DESCRIPTION

• The ECM applies an offset voltage of 0.5 volt to 

the heated oxygen sensor.

• The ECM checks for heated oxygen sensor offset 

voltage.

.

DESCRIPTIONS OF MONITOR METHODS

Heated oxygen sensor offset voltage is under speci-

fied 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)

• Not applicable

.

AC608435

Data link connector

MB991827

MB991824

MB991910

AB

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-678

DTC SET CONDITION

Logic Flow Chart

.

Check Condition

• 2 seconds or more have passed since the engine 

starting sequence was completed.

Judgement Criterion

• Heated oxygen sensor offset voltage has contin-

ued to be 0.4 volt or lower for 2 seconds.

.

FAIL-SAFE AND BACKUP FUNCTION

• None

.

OBD-II DRIVE CYCLE PATTERN

Refer to Diagnosis Function − OBD-II Drive Cycle − 

Pattern 23 

P.13A-9

.

.

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

• ECM failed. 

DIAGNOSIS

Required Special Tools:

• MB991958: Scan tool (M.U.T.-III Sub Assembly)

• MB991824: V.C.I.
• MB991827: USB Cable
• MB991910: Main Harness A

AK704300

Good

Malfunction

End

No

No

No

2secs have passed?

Heated oxygen

sensor offset voltage

< 0.4V or > 0.6V?

Start

Yes

Yes

Yes

Monitoring
conditions

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-679

STEP 1. Test the OBD-II drive cycle.

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) Carry out the test drive with the drive cycle pattern. Refer to 

DIagnostic Function − OBD-II Drive Cycle − Pattern 23 

P.13A-9

.

(4) Check the diagnostic trouble code (DTC).
Q: Is DTC P2252 set?

YES : Replace the ECM. When the ECM is replaced, 

register the ID code. Refer to GROUP 42B, ID Code 
Registration Necessity Judgment Table <Vehicles 
with KOS> 

P.42B-11

 or GROUP 42C, ID Codes 

Registration Judgment Table <Vehicles with WCM> 

P.42C-9

. 

NO :  It can be assumed that this malfunction is intermittent. 

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

Cope with Intermittent Malfunctions 

P.00-15

.

DTC P2253: Heated Oxygen Sensor Offset Circuit High Voltage

.

TECHNICAL DESCRIPTION

• The ECM applies an offset voltage of 0.5 volt to 

the heated oxygen sensor 

• The ECM checks for heated oxygen sensor offset 

voltage.

.

DESCRIPTIONS OF MONITOR METHODS

Heated oxygen sensor offset voltage is over speci-

fied 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)

• Not applicable

.

AC608435

Data link connector

MB991827

MB991824

MB991910

AB

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-680

DTC SET CONDITION

Logic Flow Chart

.

Check Condition

• 2 seconds or more have passed since the engine 

starting sequence was completed.

Judgement Criterion

• Heated oxygen sensor offset voltage has contin-

ued to be 0.6 volt or higher for 2 seconds.

.

FAIL-SAFE AND BACKUP FUNCTION

• Does not control air-fuel ratio closed loop.

.

OBD-II DRIVE CYCLE PATTERN

Refer to Diagnosis Function − OBD-II Drive Cycle − 

Pattern 23 

P.13A-9

.

.

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

• ECM failed.

DIAGNOSIS

Required Special Tools:

• MB991958: Scan tool (M.U.T.-III Sub Assembly)

• MB991824: V.C.I.
• MB991827: USB Cable
• MB991910: Main Harness A

AK704300

Good

Malfunction

End

No

No

No

2secs have passed?

Heated oxygen

sensor offset voltage

< 0.4V or > 0.6V?

Start

Yes

Yes

Yes

Monitoring
conditions