Mitsubishi Evolution X. Manual - part 612

DIAGNOSIS

TSB Revision

WIRELESS CONTROL MODULE (WCM)

42C-65

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

position.

(3) Check if DTC is set.
(4) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the DTC set?

YES : Replace WCM and register the ID codes (Refer to 

P.42C-9

).

NO :  The trouble can be an intermittent malfunction (Refer 

to GROUP 00 

− How to use 

Troubleshooting/inspection Service Points 

− How to 

Cope with Intermittent Malfunction 

P.00-15

).

DTC U0151: SRS-ECU CAN timeout

CAUTION

• If DTC U0151 is set, be sure to diagnose the 

CAN bus line.

• When replacing the ECU, always check that 

the communication circuit is normal.

.

DIAGNOSTIC FUNCTION

If no signal from SRS-ECU can be received, WCM 
sets diagnostic trouble code U0151.

.

TROUBLESHOOTING HINTS

• The CAN bus line may be defective

• The SRS-ECU may be defective

• Malfunction of WCM

DIAGNOSIS

Required Special Tools:

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

• MB991824: Vehicle Communication Interface (V.C.I.)

• MB991827: M.U.T.-III USB Cable

• MB991910: M.U.T.-III Main Harness A

DIAGNOSIS

TSB Revision

WIRELESS CONTROL MODULE (WCM)

42C-66

STEP 1. Using scan tool MB991958, diagnose the 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. Refer to "How to connect the 

Scan Tool (M.U.T.-III) 

P.42C-6

."

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

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

Diagnosis 

P.54C-14

).

STEP 2. Using scan tool MB991958, read the SRS-ECU 
diagnostic trouble code.
Check again if the DTC is set to the SRS-ECU.
Q: Is the DTC set?

YES : Troubleshoot the SRS (Refer to GROUP 52B, 

Troubleshooting 

P.52B-31

).

NO :  Go to Step 3.

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

position.

(3) Check if DTC is set.
(4) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the DTC set?

YES : Replace WCM and register the ID codes (Refer to 

P.42C-9

).

NO :  The trouble can be an intermittent malfunction (Refer 

to GROUP 00 

− How to use 

Troubleshooting/inspection Service Points 

− How to 

Cope with Intermittent Malfunction 

P.00-15

).

AC608435

Data link connector

MB991827

MB991824

MB991910

AB

DIAGNOSIS

TSB Revision

WIRELESS CONTROL MODULE (WCM)

42C-67

DTC U0154: Occupant classification-ECU CAN timeout

CAUTION

• If DTC U0154 is set, be sure to diagnose the 

CAN bus line.

• When replacing the ECU, always check that 

the communication circuit is normal.

.

DIAGNOSTIC FUNCTION

When the signals from occupant classification-ECU 
cannot be received, the WCM sets DTC U0154.

.

TROUBLESHOOTING HINTS

• The CAN bus line may be defective.

• The WCM may be defective.

• The occupant classification-ECU may be defec-

tive.

DIAGNOSIS

Required Special Tools:

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

• MB991824: Vehicle Communication Interface (V.C.I.)

• MB991827: M.U.T.-III USB Cable

• MB991910: M.U.T.-III Main Harness A

STEP 1. Using scan tool MB991958, diagnose the 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. Refer to "How to connect the 

Scan Tool (M.U.T.-III) 

P.42C-6

."

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

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

Diagnosis 

P.54C-14

).

STEP 2. Using scan tool MB991958, read the SRS-ECU 
diagnostic trouble code.
Check if DTC is set to the SRS-ECU.
Q: Is the DTC set?

YES : Troubleshoot the SRS (Refer to GROUP 52B, 

Diagnosis 

P.52B-297

).

NO :  Go to Step 3.

AC608435

Data link connector

MB991827

MB991824

MB991910

AB

DIAGNOSIS

TSB Revision

WIRELESS CONTROL MODULE (WCM)

42C-68

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

position.

(3) Check if DTC is set.
(4) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the DTC set?

YES : Replace WCM and register the ID codes (Refer to 

P.42C-9

).

NO :  The trouble can be an intermittent malfunction (Refer 

to GROUP 00 

− How to use 

Troubleshooting/inspection Service Points 

− How to 

Cope with Intermittent Malfunction 

P.00-15

).

DTC U0155: Combination meter CAN timeout

CAUTION

• If DTC U0155 is set, be sure to diagnose the 

CAN bus line.

• When replacing the ECU, always check that 

the communication circuit is normal.

.

TROUBLE JUDGMENT

If no signal from the combination meter can be 
received, WCM sets DTC U0155.

.

TROUBLESHOOTING HINTS

• Malfunction of CAN bus line

• Combination meter malfunction

• Malfunction of WCM

DIAGNOSIS

Required Special Tools:

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

• MB991824: Vehicle Communication Interface (V.C.I.)

• MB991827: M.U.T.-III USB Cable

• MB991910: M.U.T.-III Main Harness A