Mitsubishi Evolution X. Manual - part 621

DIAGNOSIS

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WIRELESS CONTROL MODULE (WCM)

42C-101

STEP 9. Check the wiring harness between the receiver 
antenna assembly connector D-14 (terminal Nos. 1, 3 and 
5) and the ground for short circuit.
(1) Disconnect receiver antenna assembly connector D-14, 

and check the wiring harness.

(2) Check the wiring harness between receiver antenna 

assembly connector D-14 (terminal No.1) and ground

OK: No continuity

(3) Check the wiring harness between receiver antenna 

assembly connector D-14 (terminal No.3) and ground

OK: No continuity

(4) Check the wiring harness between receiver antenna 

assembly connector D-14 (terminal No.5) and ground

OK: No continuity

Q: Is the wiring harness between receiver antenna 

assembly connector D-14 (terminal Nos. 1, 3 and 5) and 
the ground in good condition?
YES  : Go to Step 10.
NO (receiver antenna assembly connector D-14 terminal 
No.1 

− ground.) : Repair the wiring harness between 

receiver antenna assembly connector D-14 (terminal 
No.1) and the ground.

NO (receiver antenna assembly connector D-14 terminal 
No.3 

− ground.) : Repair the wiring harness between 

receiver antenna assembly connector D-14 (terminal 
No.3) and the ground.

NO (receiver antenna assembly connector D-14 terminal 
No.5 

− ground.) : Repair the wiring harness between 

receiver antenna assembly connector D-14 (terminal 
No.5) and the ground.

AC709707FZ

Harness side: D-14

AC709707FW

Harness side: D-14

AC709707FV

Harness side: D-14

DIAGNOSIS

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WIRELESS CONTROL MODULE (WCM)

42C-102

STEP 10. Retest the system.
Replace the receiver antenna assembly. Check if the keyless 
entry system works normally.
Q: Is the check result normal?

YES : Intermittent malfunction (Refer to GROUP 00, How to 

Use Troubleshooting/Inspection Service Points - How 
to Cope with Intermittent Malfunction 

P.00-15

).

NO :  Replace WCM and register the ID codes (Refer to 

P.42C-9

).

Inspection Procedure 6: Keyless entry hazard light answerback function, the dome light answerback 
function or the horn answerback function does not work normally.

CAUTION

Before replacing the ECU, ensure that the power 
supply circuit, the ground circuit and the com-
munication circuit are normal.

.

TECHNICAL DESCRIPTION (COMMENT)

If the hazard warning light and the dome light works 
normally, ETACS-ECU may be faulty. Also, the 
answerback function may have been disabled using 
the customization function.

.

TROUBLESHOOTING HINTS

• The turn signal lights may be defective

• The dome light may be defective

• The horn may be defective

• The  ETACS-ECU may be defective

• The wiring harness or connectors may have 

loose, corroded, or damaged terminals, or termi-
nals pushed back in the connector

DIAGNOSIS

STEP 1. Verify the operation hazard warning light.
Check that the hazard warning light illuminate normally.
Q: Is the check result normal?

YES : Go to Step 2.
NO :  Refer to GROUP 54A 

− inspection procedure 1: 

"Hazard warning light does not illuminate 

P.54A-266

."

STEP 2. Verify the operation of the dome light.
Check that the dome lights illuminate normally.
Q: Is the check result normal?

YES : Go to Step 3.
NO :  Refer to GROUP 54A 

− inspection procedure 1 "The 

front dome light does not illuminate normally 

P.54A-243

." or inspection procedure 2 "The rear 

dome light does not illuminate normally 

P.54A-248

."

STEP 3. Verify the horn.
Check that the horn normally.
Q: Is the check result normal?

YES : Go to Step 4.
NO :  Replace the horn (Refer to GROUP 54A, Horn 

P.54A-268

).

DIAGNOSIS

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WIRELESS CONTROL MODULE (WCM)

42C-103

STEP 4. Check the operation of the keyless entry system.
Operate the transmitter and check that all doors lock and 
unlock.
Q: Is the check result normal?

YES : Go to Step 5.
NO :  Refer to inspection procedure 5: "Keyless entry 

system does not work 

P.42C-93

."

STEP 5. Check the customize function (Hazard light 
answerback).
Check that any one of the followings other than "Lock: 0, 
Unlock: 0" is set for "Hazard answerback" with a customization 
function.

• Lock:1, Unlock:2

• Lock:1, Unlock:0

• Lock:0, Unlock:2

• Lock:2, Unlock:1

• Lock:2, Unlock:0

• Lock:0, Unlock:1

Q: Is the check result normal?

YES : Go to Step 6.
NO :  Set "Hazard answerback" to any one other than 

"Lock: 0, Unlock: 0" with a customization function 
(Refer to 

P.42C-126

).

STEP 6. Check the customize function (Horn answerback).
Check that any one of the followings other than "Not sound 
horn" is set for "Horn chirp by keyless" with a customization 
function.

• Lock any time

• W lock any time

Q: Is the check result normal?

YES : Go to Step 7.
NO :  Set "Horn chirp by keyless" to any one other than "Not 

sound horn" with a customization function (Refer to 

P.42C-126

).

STEP 7. Check of the troubles
Check if the keyless entry answerback function works normally.
Q: Is the check result normal?

YES : Intermittent malfunction (Refer to GROUP 00, How to 

Use Troubleshooting/Inspection Service Points - How 
to Cope with Intermittent Malfunction 

P.00-15

).

NO :  Replace ETACS-ECU.

DIAGNOSIS

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WIRELESS CONTROL MODULE (WCM)

42C-104

Inspection Procedure 7: The timer lock function does not work after the doors have been unlocked by 
the keyless entry system.

CAUTION

Before replacing the ECU, ensure that the power 
supply circuit, the ground circuit and the com-
munication circuit are normal.

.

TECHNICAL DESCRIPTION (COMMENT)

If the timer lock function does not work normally, the 
keyless entry transmitter input signal circuit or 
ETACS-ECU may be faulty.

.

TROUBLESHOOTING HINTS

• The keyless entry transmitter may be defective

• The  ETACS-ECU may be defective

• The wiring harness or connectors may have 

loose, corroded, or damaged terminals, or termi-
nals pushed back in the connector

DIAGNOSIS

STEP 1. Check the operation of the keyless entry system.
Operate the transmitter and check that all doors lock and 
unlock.
Q: Is the check result normal?

YES : Go to Step 2.
NO :  Refer to inspection procedure 5: "Keyless entry 

system does not work 

P.42C-93

."

STEP 2. Check the customize function.
The "Timer lock timer" has been set to one of the followings 
with the customization function. Check if the doors are locked 
at the set period.

• 30sec

• 60sec

• 120sec

• 180sec

Q: Is the check result normal?

YES : Intermittent malfunction (Refer to GROUP 00 

− How to 

Use Troubleshooting/Inspection Service Points - How 
to Cope with Intermittent Malfunction 

P.00-15

).

NO :  Replace ETACS-ECU.