Mitsubishi Lancer Evolution X. Manual - part 343

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-437

DIAGNOSIS

Required Special Tools:

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

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

• MB992110: Power Plant ECU Check Harness

STEP 1. Using scan tool MB991958, check actuator test 
item 10: Evaporative Emission Purge Solenoid.

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 actuator test mode for item 

10, Evaporative emission purge solenoid.

• An operation sound should be heard and vibration 

should be felt when the evaporative emission purge 
solenoid is operated.

(4) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the solenoid operating properly?

YES : It can be assumed that this malfunction is intermittent. 

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

Cope with Intermittent Malfunctions 

P.00-15

.

NO :  Go to Step 2.

STEP 2. Check harness connector B-12 at the evaporative 
emission purge solenoid for damage.
Q: Is the harness connector in good condition?

YES : Go to Step 3.
NO :  Repair or replace it. Refer to GROUP 00E, Harness 

Connector Inspection 

P.00E-2

. Then go to Step 10.

AC608435

Data link connector

MB991827

MB991824

MB991910

AB

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-438

STEP 3. Check the evaporative emission purge solenoid.
(1) Disconnect the evaporative emission purge solenoid 

connector B-12.

(2) Measure the resistance between evaporative emission 

purge solenoid side connector terminal No. 1 and No. 2.

Standard value: 22 − 26 Ω [at 20° C (68° F)]

Q: Is the measured resistance between 22 and 26 Ω [at 

20° C (68° F)]?
YES : Go to Step 4.
NO :  Replace the evaporative emission purge solenoid. 

Then go to Step 10.

STEP 4. Measure the power supply voltage at evaporative 
emission purge solenoid harness side connector B-12.
(1) Disconnect the connector B-12 and measure at the harness 

side.

(2) Turn the ignition switch to the "ON" position.
(3) Measure the voltage between terminal No. 2 and ground.

• Voltage should be battery positive voltage.

(4) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is battery positive voltage (approximately 12 volts) 

present?
YES : Go to Step 6.
NO :  Go to Step 5.

STEP 5. Check harness connector A-34X at MFI relay for 
damage.
Q: Is the harness connector in good condition?

YES : Check harness connector A-39 at intermediate 

connector for damage, and repair or replace as 
required. Refer to GROUP 00E, Harness Connector 
Inspection 

P.00E-2

. If intermediate connector is in 

good condition, repair harness wire between MFI 
relay connector A-34X (terminal No. 2) and 
evaporative emission purge solenoid connector B-12 
(terminal No. 2) because of open circuit or short 
circuit to ground. Then go to Step 10.

NO :  Repair or replace it. Refer to GROUP 00E, Harness 

Connector Inspection 

P.00E-2

. Then go to Step 10.

STEP 6. Check harness connector B-09 at ECM for 
damage.
Q: Is the harness connector in good condition?

YES : Go to Step 7.
NO :  Repair or replace it. Refer to GROUP 00E, Harness 

Connector Inspection 

P.00E-2

. Then go to Step 10.

1 2

AK202961

Evaporative emission
purge solenoid connector

AC

AK303144

1

2

B-12 harness 
connector: 
component side

AE

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-439

STEP 7. Measure the power supply voltage at ECM 
connector B-09 by using power plant ECU check harness 
special tool MB992110.
(1) Disconnect all ECM connectors. Connect the power plant 

ECU check harness special tool MB992110 between the 
separated connectors.

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

(3) Measure the voltage between terminal No. 37 and ground.

• Voltage should be battery positive voltage.

(4) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is battery positive voltage (approximately 12 volts) 

present?
YES : Go to Step 8.
NO :  Repair harness wire between evaporative emission 

purge solenoid connector B-12 (terminal No. 1) and 
ECM connector B-09 (terminal No. 37) because of 
open circuit or short circuit to ground. Then go to Step 
10.

STEP 8. Check for harness damage between MFI relay 
connector A-34X (terminal No. 2) and evaporative emission 
purge solenoid connector B-12 (terminal No. 2).
NOTE: Check harness after checking intermediate connector 
A-39. If intermediate connector is damaged, repair or replace it. 
Refer to GROUP 00E, Harness Connector Inspection 

P.00E-2

. 

Then go to Step 10.
Q: Is the harness wire in good condition?

YES : Go to Step 9.
NO :  Repair it. Then go to Step 10.

AK604040

ECM

AB

Body side harness 

MB992110

AK604209

16 15 14 13 12 11 10 9 8 7 6 5 4 3

2

1

32 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17

48 47 46 45 44 43 42 41 40 39 38 37 36 35 34 33

64 63 62 61 60 59 58 57 56 55 54 53 52 51 50 49

AB

Power plant ECU
check harness connector

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-440

STEP 9. Check for harness damage between evaporative 
emission purge solenoid connector B-12 (terminal No. 1) 
and ECM connector B-09 (terminal No. 37).
Q: Is the harness wire in good condition?

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 10.

NO :  Repair it. Then go to Step 10.

STEP 10. Test the OBD-II drive cycle.
(1) Carry out a test drive with the drive cycle pattern. Refer to 

Diagnostic Function − OBD-II Drive Cycle − Pattern 23 

P.13A-9

.

(2) Check the diagnostic trouble code (DTC).
Q: Is DTC P0443 set?

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