Mitsubishi Evolution X. Manual - part 810

DIAGNOSIS

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ACTIVE SKID CONTROL SYSTEM (ASC)

35C-247

STEP 10. Check of fuse No. 17 and fusible link No. 34
Visually check for open circuit in the fuse No. 17 and the fusible 
link No. 34.
Q: Is the check result normal?

YES : Go to Step 16.
NO :  Go to Step 11.

STEP 11. Connector check: C-41 intermediate connector, 
C-43 joint connector, C-46 ETACS-ECU connector, C-103 
joint connector, C-130 intermediate connector, C-309 
ETACS-ECU connector and C-315 ETACS-ECU connector
Q: Is the check result normal?

YES : Go to Step 12.
NO :  Repair the connector. Then, replace fuse No. 17 or 

fusible link No. 34.

STEP 12. Wiring harness check between C-309 
ETACS-ECU connector and fusible link No. 34.
(1) Remove fusible link No. 34.
(2) Disconnect ETACS-ECU connector C-309, and measure at 

the wiring harness side.

(3) Check the continuity (short to ground) between terminal No. 

1 and the ground.

OK: No continuity

Q: Is the check result normal?

YES : Go to Step 13.
NO :  Repair the wiring harness between C-309 

ETACS-ECU connector terminal No. 1 and fusible link 
No. 34. Then, replace fuse No. 17 or fusible link No. 
34.

STEP 13. Wiring harness check between C-315 
ETACS-ECU connector and C-103 joint connector.
(1) Disconnect the C-103 joint connector.
(2) Disconnect ETACS-ECU connector C-315, and measure at 

the wiring harness side.

(3) Check the continuity (short to ground) between terminal No. 

4 and the ground.

OK: No continuity

Q: Is the check result normal?

YES : Go to Step 14.
NO :  Repair the wiring harness between C-315 

ETACS-ECU connector terminal No. 4 and C-103 
joint connector terminal No.18. Then, replace fuse 
No. 17 or fusible link No. 34.

DIAGNOSIS

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ACTIVE SKID CONTROL SYSTEM (ASC)

35C-248

STEP 14. Wiring harness check between the C-103 joint 
connector and the C-46 S-AWC-ECU connector.
(1) Disconnect the C-46 S-AWC-ECU connector.
(2) Disconnect the C-103 joint connector, and measure at the 

wiring harness side.

(3) Check the continuity (short to ground) between terminal No. 

16 and the ground.

OK: No continuity

Q: Is the check result normal?

YES : Go to Step 15.
NO :  Repair the wiring harness between C-103 joint 

connector terminal No.16 and C-46 S-AWC-ECU 
connector terminal No.12. Then, replace fuse No. 17 
or fusible link No. 34.

STEP 15. Wiring harness check between the C-103 joint 
connector and the A-05 ASC-ECU connector.
(1) Disconnect ASC-ECU connector A-05.
(2) Disconnect the C-103 joint connector, and measure at the 

wiring harness side.

(3) Check the continuity (short to ground) between terminal 

No.17 and the ground.

OK: No continuity

Q: Is the check result normal?

YES : Replace the fuse No. 17 or the fusible link No. 34. 

Then, go to Step 20.

NO :  Repair the wiring harness between C-103 joint 

connector terminal No.17 and A-05 ASC-ECU 
connector terminal No.2. Then, replace fuse No. 17 or 
fusible link No. 34.

DIAGNOSIS

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ACTIVE SKID CONTROL SYSTEM (ASC)

35C-249

STEP 16. Voltage measurement at A-05 ASC-ECU 
connector
(1) Disconnect the connector, connect the ASC check harness 

(Special tool: MB991997) to the wiring harness-side 
connector, and measure the voltage at the special tool 
connector side.
NOTE: Do not connect the special tool to ASC-ECU.

(2) Measure the voltage between the terminal No. 2 and the 

body ground.

OK: System voltage

Q: Is the check result normal?

YES : Go to Step 20.
NO :  Go to Step 17.

STEP 17. Measure the voltage at the C-309 ETACS-ECU 
connector.
(1) Disconnect the connector, and measure at the wiring 

harness-side connector.

(2) Measure the voltage between the terminal No. 1 and the 

body ground.

OK: System voltage

Q: Is the check result normal?

YES : Go to Step 18.
NO :  Repair the wiring harness between C-309 

ETACS-ECU connector terminal No. 1 and the fusible 
link No. 34.

STEP 18. Measure the voltage at the C-315 ETACS-ECU 
connector.
(1) Without disconnecting the connector, measure by 

backprobing.

(2) Measure the voltage between the terminal No. 4 and the 

body ground.

OK: System voltage

Q: Is the check result normal?

YES : Go to Step 20.
NO :  Go to Step 19.

AC400817CN

ASC-ECU

MB991997

A-05 ASC-ECU 
harness connector

Check harness

DIAGNOSIS

TSB Revision

ACTIVE SKID CONTROL SYSTEM (ASC)

35C-250

STEP 19. Wiring harness check between A-05 ASC-ECU 
connector terminal No. 2 and C-315 ETACS-ECU connector 
terminal No. 4

• Check for open circuit.

Q: Is the check result normal?

YES : Go to Step 20.
NO  :  Repair the wiring harness.

STEP 20. Resistance measurement at A-05 ASC-ECU 
connector
(1) Disconnect the connector, connect the ASC check harness 

(Special tool: MB991997) to the wiring harness-side 
connector, and measure the voltage at the special tool 
connector side.
NOTE: Do not connect the special tool to ASC-ECU.

(2) Measure the resistance between the terminal No. 16 and 

the body ground as well as between the terminal No. 47 
and the body ground.

OK: Continuity exists (2 

Ω or less)

Q: Is the check result normal?

YES : Go to Step 21.
NO  :  Repair the wiring harness.

STEP 21. Retest the system.
Q: Is the communication with scan tool MB991958 

possible?
YES : Intermittent malfunction. (Refer to GROUP 00 

− How 

to Cope with Intermittent Malfunction 

P.00-15

.)

NO :  Check that the M.U.T.-III connection cable is properly 

connected, and that the V.C.I. switch is turned ON. 
Then, replace the hydraulic unit (integrated with 
ASC-ECU).(Refer to 

P.35C-272

.) Then go to Step 22.

STEP 22. Retest the system.
Q: Is the communication with scan tool MB991958 

possible?
YES : Return to Step 1.
NO :  This diagnosis is complete.

AC400817CO

ASC-ECU

MB991997

A-05 ASC-ECU 
harness connector

Check harness