Mitsubishi Lancer Evolution X. Manual - part 405

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-685

STEP 2. Recheck for diagnostic trouble code.
Check again if the DTC is set.
(1) Erase the DTC.
(2) Turn the ignition switch to the "ON" position.
(3) Check if the DTC is set.
(4) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is DTC U0001 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

. Then go to Step 3.

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

.

STEP 3. Recheck for diagnostic trouble code.
Check again if the DTC is set.
(1) Erase the DTC.
(2) Turn the ignition switch to the "ON" position.
(3) Check if DTC is set.
(4) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is DTC U0001 set?

YES : Replay the troubleshooting.
NO :  The inspection is complete.

DTC U0101: TC-SST-ECU Time-out <TC-SST>

CAUTION

• If the ECM output the DTC U0101, make sure 

to diagnose the CAN bus line.

• Before replacing the ECU, make sure that the 

communication circuit is operating normally.

.

DESCRIPTIONS OF MONITOR METHODS

There is no data from TC-SST-ECU for the specified 

time. (TC-SST-ECU also detect communication 
error with ECM.)

.

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

.

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-686

DTC SET CONDITIONS

Logic Flow Chart

Check Condition

• Battery positive voltage is between 10 and 16.5 

volts.

Judgement Criterion

• Unable to receive TC-SST-ECU signals through 

the CAN bus line for 4 seconds.

.

COMMENT

Current Trouble

• Some of the possible causes are a harness or 

connector damage between the ECM and the 
TC-SST-ECU on the CAN bus line, a failure in the 
TC-SST-ECU power supply system, a failure in 
the TC-SST-ECU, or a failure in the ECM.

AK604369

Start

Yes

Yes

Yes

No

No

No

Continuous failure

for specified time

Malfunction

End

Good

Monitoring
conditions

Communication status

fails

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-687

Past Trouble

• Proceed to troubleshoot based on a harness or 

connector damage on the CAN bus line between 
the ECM and TC-SST-ECU, and a failure in the 
TC-SST-ECU power supply system. Refer to 
"How to cope with past trouble" (Refer to GROUP 
00, How to Use Troubleshooting/Inspection Ser-
vice Points − How to Treat Past Trouble 

P.00-16

).

NOTE: If a malfunction occurred in the past, a failure 
cannot be discovered through the M.U.T. 

−

 III CAN 

bus diagnosis even if there might be a problem with 
the CAN bus. In this case, refer to GROUP 00, How 
to Use Troubleshooting/Inspection Service Points 

−

 

How to Cope with Intermittent Malfunctions 

P.00-15

. 

Furthermore, it is possible to narrow down the areas 
of the possible failures from the DTCs that are output 
by the ECUs, which are communicating on the CAN 
bus (Refer to GROUP 54C, CAN bus line Diagnos-
tics Flow 

P.54C-9

).

.

FAIL-SAFE AND BACKUP FUNCTION

• None

.

OBD-II DRIVE CYCLE PATTERN

None.

.

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

• CAN line harness damage or connector damage.
• TC-SST-ECU failed.
• 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

STEP 1. Using scan tool MB991958, diagnose CAN bus 
line.

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) Diagnose CAN bus line.
(4) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the CAN bus line normal?

YES : Go to Step 2.
NO :  Repair the CAN bus line. Refer to GROUP 54C, Can 

Bus Diagnostics Table 

P.54C-15

. Then go to Step 6.

AC608435

Data link connector

MB991827

MB991824

MB991910

AB

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-688

STEP 2. Using scan tool MB991958, read the diagnostic 
trouble code (DTC).
(1) Turn the ignition switch to the "ON" position.
(2) Read the TC-SST-DTC.
(3) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the TC-SST-DTC set?

YES : Refer to GROUP 22C, Diagnosis <TC-SST> − 

Diagnostic Trouble Code Chart 

P.22C-15

.

NO :  Go to Step 3.

STEP 3. Using scan tool MB991958, read the diagnostic 
trouble code (DTC).
(1) Turn the ignition switch to the "ON" position.
(2) Read the S-AWC-DTC, Shift lever-DTC, ASC-DTC and 

ETACS-DTC.

(3) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is DTC U0101 set?

YES : Go to Step 4.
NO :  Go to Step 5.

STEP 4. Using scan tool MB991958, read the diagnostic 
trouble code (DTC).
(1) Turn the ignition switch to the "ON" position.
(2) After the MFI-DTC has been deleted, read the MFI-DTC 

again.

(3) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is DTC U0101 set?

YES : Replace the TC-SST-ECU. Then go to Step 6.
NO :  It can be assumed that this malfunction is intermittent 

of CAN bus line between ECM and TC-SST-ECU. 
Refer to GROUP 00, How to Use 
Troubleshooting/Inspection Service Points − How to 

Cope with Intermittent Malfunctions 

P.00-15

.