Mitsubishi Evolution X. Manual — part 601

DIAGNOSIS

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WIRELESS CONTROL MODULE (WCM)

42C-21

DTC B1A10: Keyless/KOS key 1 low battery

DTC B1A11: Keyless/KOS key 2 low battery

DTC B1A12: Keyless/KOS key 3 low battery

DTC B1A13: Keyless/KOS key 4 low battery

DTC B1A14: Keyless key 5 low battery

DTC B1A15: Keyless key 6 low battery

DTC B1A16: Keyless key 7 low battery

DTC B1A17: Keyless key 8 low battery

CAUTION

When replacing the ECU, always check that the
communication circuit is normal.

.

DTC SET CONDITION

WCM sets DTC B1A10, B1A11, B1A12, B1A13,
B1A14, B1A15, B1A16, or B1A17 when it receives
low battery voltage signal from the transmitter.

.

TECHNICAL DESCRIPTION (COMMENT)

• B1A10: WCM determines that the abnormality is

present when it receives low battery voltage sig-
nal from the transmitter 1 (the first transmitter
registered in WCM) five consecutive times.

• B1A11: WCM determines that the abnormality is

present when it receives low battery voltage sig-
nal from the transmitter 2 (the second transmitter
registered in WCM) five consecutive times.

• B1A12: WCM determines that the abnormality is

present when it receives low battery voltage sig-
nal from the transmitter 3 (the third transmitter
registered in WCM) five consecutive times.

• B1A13: WCM determines that the abnormality is

present when it receives low battery voltage sig-
nal from the transmitter 4 (the fourth transmitter
registered in WCM) five consecutive times.

• B1A14: WCM determines that the abnormality is

present when it receives low battery voltage sig-
nal from the transmitter 5 (the fifth transmitter
registered in WCM) five consecutive times.

• B1A15: WCM determines that the abnormality is

present when it receives low battery voltage sig-
nal from the transmitter 6 (the sixth transmitter
registered in WCM) five consecutive times.

• B1A16: WCM determines that the abnormality is

present when it receives low battery voltage sig-
nal from the transmitter 7 (the seventh transmitter
registered in WCM) five consecutive times.

• B1A17: WCM determines that the abnormality is

present when it receives low battery voltage sig-
nal from the transmitter 8 (the eighth transmitter
registered in WCM) five consecutive times.

.

TROUBLESHOOTING HINTS

• Battery failure in the transmitter

• Malfunction of the transmitter

• Malfunction of WCM

DIAGNOSIS

STEP 1. Replace the battery in the transmitter
and recheck the diagnostic trouble code.
Replace the battery in the transmitter by which the
DTC is set with a new one, and recheck if the DTC is
set (Refer to

P.42C-129

).

(1) Replace the battery in the transmitter by which

the DTC is set.

(2) Use the transmitter to lock/unlock the doors.
(3) Check if the DTC is set.

Q: Is the DTC set?

YES :

Go to Step 2.

NO :

The diagnosis is complete (Discharged
battery).

STEP 2. Replace the transmitter and recheck the
diagnostic trouble code.
Replace the transmitter by which the DTC is set with
a new one, register the key ID and the keyless entry
secret code (Refer to

P.42C-114

), and recheck if the

DTC is set.
(1) Use the transmitter to lock/unlock the doors.
(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 diagnosis is complete.

DIAGNOSIS

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WIRELESS CONTROL MODULE (WCM)

42C-22

DTC B1A24: Key ID not registered

CAUTION

• When the DTC B1A24 is set, be sure to diag-

nose the CAN bus line.

• When replacing the ECU, always check that

the communication circuit is normal.

.

DTC SET CONDITION

WCM sets DTC B1A24 when the key ID was not reg-
istered in it.

.

TECHNICAL DESCRIPTION (COMMENT)

WCM determines that the abnormality is present, if
the ignition key's key ID is not registered in WCM
when the ignition switch is turned ON.

.

TROUBLESHOOTING HINTS

• Key ID not registered

• Malfunction of the ignition key

• 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

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

).

AC608435

Data link connector

MB991827

MB991824

MB991910

AB

DIAGNOSIS

TSB Revision

WIRELESS CONTROL MODULE (WCM)

42C-23

STEP 2. 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 : Replace WCM and register the ID codes (Refer to

P.42C-9

).

NO : The procedure is complete.

DTC B1A25: Key ID unmatched

CAUTION

When the DTC B1A25 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 B1A25 when the received key ID is
different from the one registered in it.

.

TECHNICAL DESCRIPTION (COMMENT)

WCM determines that the abnormality is present, if
the key ID for the ignition key does not match the one
registered in WCM when the ignition switch is turned
ON.

.

TROUBLESHOOTING HINTS

• Malfunction of the ignition key

• Accessory key not registered

• Accessory WCM not registered

• Key is registered to another vehicle

• 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-24

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. 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 3.
NO : The procedure is complete.

STEP 3. Replace the ignition key and recheck the
diagnostic trouble code.
Replace the ignition key by which the DTC is set with the other
key, 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 4.
NO : Go to Step 5.

AC608435

Data link connector

MB991827

MB991824

MB991910

AB