Mitsubishi Evolution X. Manual - part 231

ENGINE COOLING DIAGNOSIS

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ENGINE COOLING

14-11

STEP 8. Check the harness wire between radiator fan relay 
connector A-35X terminal number 1 and ETACS-ECU 
connector C-312 terminal number 2, between condenser 
fan relay connector A-36X terminal number 1 and 
ETACS-ECU connector C-312 terminal number 8, between 
fan control relay connector A-37X terminal number 3 and 
ETACS-ECU connector C-312 terminal number 9, for 
damage.
Q: Is the harness wires in good condition?

YES : Go to Step 9.
NO :  Repair the damaged harness wire. Then go to Step 

22.

STEP 9. Check the radiator fan relay, condenser fan relay 
and fan control relay.
Refer to 

P.14-19

.

Q: Is the relay in good condition?

YES : Go to Step 10.
NO :  Replace the damaged relay. Then go to Step 22.

STEP 10. Check the fusible link number 28 and fusible link 
number 29.
Q: Is the fusible link in good condition?

YES : An intermittent malfunction is suspected (Refer to 

GROUP 00, How to use troubleshooting 

− How to 

Cope with Intermittent Malfunction 

P.00-15

).

NO :  Replace the damaged fusible link. Then go to Step 

22.

STEP 11. Check the radiator fan relay connector A-35X, 
condenser fan relay connector A-36X, fan control relay 
connector A-37X, radiator fan motor connector A-45 and 
condenser fan motor connector A-47, for loose, corroded 
or damaged terminals, or terminals pushed back in the 
connector.
Refer to GROUP 00E, Harness Connector Inspection 

P.00E-2

.

Q: Is the connectors and terminals in good condition?

YES : Go to Step 12.
NO :  Repair or replace damaged connectors. Then go to 

Step 22.

STEP 12. Check the harness wire between fusible link 
number 28 and condenser fan relay connector A-36X 
terminal number 4, between fusible link number 29 and 
radiator fan relay connector A-35X terminal number 4, for 
damage.
Q: Is the harness wires in good condition?

YES : Go to Step 13.
NO :  Repair the damaged harness wire. Then go to Step 

22.

ENGINE COOLING DIAGNOSIS

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ENGINE COOLING

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STEP 13. Check the harness wire between radiator fan 
relay connector A-35X terminal number 2 and radiator fan 
motor connector A-45 terminal number 1, between 
condenser fan relay connector A-36X terminal number 2 
and condenser fan motor connector A-47 terminal number 
1, for damage.
Q: Is the harness wires in good condition?

YES : Go to Step 14.
NO :  Repair the damaged harness wire. Then go to Step 

22.

STEP 14. Check the harness wire between radiator fan 
motor connector A-45 terminal number 2 and fan control 
relay connector A-37X terminal number 2, between 
condenser fan motor connector A-47 terminal number 2 
and body ground, for damage.
Q: Is the harness wires in good condition?

YES : Go to Step 15.
NO :  Repair the damaged harness wire. Then go to Step 

22.

STEP 15. Check the harness wire between fan control relay 
connector A-37X terminal number 4 and condenser fan 
motor connector A-47 terminal number 1, between fan 
control relay connector A-37X terminal number 5 and body 
ground, for damage.
Q: Is the harness wires in good condition?

YES : Go to Step 16.
NO :  Repair the damaged harness wire. Then go to Step 

22.

STEP 16. Check the radiator fan relay, condenser fan relay 
and fan control relay.
Refer to 

P.14-19

.

Q: Is the relay in good condition?

YES : Go to Step 17.
NO :  Replace the damaged relay. Then go to Step 22.

STEP 17. Check the radiator fan motor and condenser fan 
motor.

• Check the output line for short or open circuit.

Refer to 

P.14-21

.

Q: Is the fan motor in good condition?

YES : Go to Step 18.
NO :  Replace the damaged fan motor (Refer to 

P.14-31

). 

Then go to Step 22.

ENGINE COOLING DIAGNOSIS

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ENGINE COOLING

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STEP 18. Using scan tool MB991958, read the ETACS 
system diagnostic trouble code (DTC).
Using scan tool to read the ETACS system DTC (Refer to 
GROUP 54A, ETACS, Troubleshooting 

− Diagnostic Function 

P.54A-579

).

Q: Is any DTC set?

YES : Replace the ETACS-ECU (Refer to GROUP 54A, 

ETACS-ECU 

P.54A-676

). Then go to Step 22.

NO :  Go to Step 19.

STEP 19. Using scan tool MB991958, check the MFI system 
actuator test.
Using scan tool to check the MFI system actuator test (Refer to 
GROUP 13A, MFI Diagnosis 

− Diagnostic Function 

P.13A-9

).

• Item 14: Cooling fan

(Refer to GROUP 13A, MFI Diagnosis 

− Actuator Test Refer-

ence Table 

P.13A-871

)

Q: Is the check result normal?

YES : Go to Step 21.
NO :  Go to Step 20.

STEP 20. Using scan tool MB991958, read the MFI system 
diagnostic trouble code (DTC).
Using scan tool to read the MFI system DTC (Refer to GROUP 
13A, MFI Diagnosis 

− Diagnostic Function 

P.13A-9

).

Q: Is any DTC set?

YES : Replace the ECM (Refer to GROUP 13A, ECM 

P.13A-920

). Then go to Step 22.

NO :  Go to Step 21.

STEP 21. Check the symptoms.
Q: Does the radiator fan and condenser fan operate 

normal?
YES : An intermittent malfunction is suspected (Refer to 

GROUP 00, How to use troubleshooting 

− How to 

Cope with Intermittent Malfunction 

P.00-15

).

NO :  Replace the ECM (Refer to GROUP 13A, ECM 

P.13A-920

). Then go to Step 22.

STEP 22. Check the symptoms.
Q: Does the radiator fan and condenser fan operate 

normal?
YES : The procedure is complete.
NO :  Return to Step 1.

SPECIAL TOOLS

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ENGINE COOLING

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SPECIAL TOOLS

M1141000601119

Tool

Tool number and name Supersession

Application

MB991958

a: MB991824
b: MB991827
c: MB991910
d: MB991911
e: MB991914
f: MB991825
g: MB991826

Scan tool (M.U.T.-III sub 
assembly)

a: Vehicle 

communication 
interface (V. C. I.) 

b: M.U.T.-III USB cable
c: M.U.T.-III main 

harness A (Vehicles 
with CAN 
communication 
system)

d: M.U.T.-III main 

harness B (Vehicles 
without CAN 
communication 
system)

e: M.U.T.-III main 

harness C (for Daimler 
Chrysler models only)

f: M.U.T.-III 

measurement adapter

g: M.U.T.-III trigger 

harness

MB991824-KIT
NOTE: g: MB991826 
M.U.T.-III Trigger 
Harness is not 
necessary when 
pushing V.C.I. ENTER 
key.

CAUTION

For vehicles with CAN 
communication, use 
M.U.T.-III main harness A 
to send simulated vehicle 
speed. If you connect 
M.U.T.-III main harness B 
instead, the CAN 
communication does not 
function correctly.

• Checking diagnostic 

trouble code (DTC).

• Checking actuator test.

MB991910

MB991826

MB991958

MB991911

MB991914

MB991824

MB991827

MB991825

Do not use

a

b

c

d

e

f

g

Do not use