Mitsubishi Evolution X. Manual - part 602

DIAGNOSIS

TSB Revision

WIRELESS CONTROL MODULE (WCM)

42C-25

STEP 4. Register the key ID and recheck the diagnostic 
trouble code.
Register the key ID of the ignition key (refer to 

P.42C-9

), and 

recheck if the DTC is set.
(1) Turn the ignition switch from the "LOCK" (OFF) position to 

the "ON" position.

(2) Check if the DTC is set.
Q: Is the DTC set?

YES : Go to Step 5.
NO :  The procedure is complete.

STEP 5. Replace the ignition key and recheck the 
diagnostic trouble code.
Replace the ignition key with a new one, register the key ID and 
keyless ID of the new key, (refer to 

P.42C-9

), and recheck if the 

DTC is set.
(1) Turn the ignition switch from the "LOCK" (OFF) position to 

the "ON" position.

(2) Check if the DTC is set.
Q: Is the DTC set?

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

P.42C-9

).

NO :  The procedure is complete.

DTC B1A28: Engine control module authenticate error

CAUTION

• When DTC B1A28 is set, be sure to diagnose 

the CAN bus line.

• When replacing the ECU, always check that 

the communication circuit is normal.

.

DTC SET CONDITION

WCM sets DTC B1A28 when the ignition key certifi-
cation result and the engine control module starting 
condition do not match.

.

TECHNICAL DESCRIPTION (COMMENT)

WCM determines that the abnormality is present, if 
the key certification result and the engine  control 
module starting condition do not match after the 
engine start permission communication is com-
pleted.

.

TROUBLESHOOTING HINTS

• Malfunction of CAN bus line

• Malfunction of WCM

• Malfunction of engine control module

• VIN registered in engine control module 

unmatched

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

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WIRELESS CONTROL MODULE (WCM)

42C-26

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 
connecting 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) 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 engine 
control module diagnostic trouble code.
Check again if the DTC is set to the engine control module.
Q: Is the DTC set?

YES : Troubleshoot the MFI system (Refer to GROUP 13A, 

Diagnostic trouble code chart 

P.13A-44

).

NO :  Go to Step 3.

STEP 3. Using scan tool MB991958, read the diagnostic  
trouble code. 
Check if the DTC is set to the WCM.
(1) Turn the ignition switch from the "LOCK" (OFF) position to 

the "ON" position.

(2) Check if the DTC is set.
Q: Is DTC B1761 or B2206 set other than B1A28?

YES : Perform the troubleshooting for each DTC. Refer to 

P.42C-18

 <B1761> and 

P.42C-35

 <B2206>.

NO :  Go to Step 4.

AC608435

Data link connector

MB991827

MB991824

MB991910

AB

DIAGNOSIS

TSB Revision

WIRELESS CONTROL MODULE (WCM)

42C-27

STEP 4. Recheck for diagnostic trouble code.
Check again if the DTC is set to the WCM.
(1) Turn the ignition switch from the "LOCK" (OFF) position to 

the "ON" position.

(2) Check if the DTC is set.
Q: Is the DTC set?

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

P.42C-9

). Then go to Step 5.

NO :  The diagnosis is complete.

STEP 5. Recheck for diagnostic trouble code.
Check again if the DTC is set to the WCM.
(1) Turn the ignition switch from the "LOCK" (OFF) position to 

the "ON" position.

(2) Check if the DTC is set.
Q: Is the DTC set?

YES : Replace the engine control module and record VIN 

(Refer to GROUP 00 

− How to Perform Vehicle 

Identification Number (VIN) Writing 

P.00-27

).

NO :  The procedure is complete.

DTC B1A35: Transponder read error

CAUTION

• When DTC B1A35 is set, be sure to diagnose 

the CAN bus line.

• When replacing the ECU, always check that 

the communication circuit is normal.

.

DTC SET CONDITION

WCM sets DTC B1A35 when it cannot receive data 
from the transponder.

.

TECHNICAL DESCRIPTION (COMMENT)

WCM determines that the abnormality is present, if it 
cannot receive the key ID for the ignition key when 
the ignition switch is turned ON.

.

TROUBLESHOOTING HINTS

• Malfunction of the ignition key

• Malfunction of WCM

• Interference of the key ID

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-28

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 
connecting 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) 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. Check the ignition key inserted in the key cylinder 
for interference.
Q: Are there other ignition keys or anything that interferes 

with the communication (things that generate radio 
waves such as magnets or air-cleaning device that has 
a power plug) near the ignition key inserted in the key 
cylinder?
YES : Move away or remove other ignition keys or anything 

that interferes with the communication, and go to Step 
3. 

NO :  Go to Step 3.

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

the "ON" position.

(2) Check if the DTC is set.
Q: Is the DTC set?

YES : Go to Step 4.
NO :  The procedure is complete.

AC608435

Data link connector

MB991827

MB991824

MB991910

AB