GENERAL INFORMATION
The wireless control module (WCM) is a system that integrates the keyless entry function with which remote operation (opening/closing of all doors, opening of trunk lid < LANCER >, liftgate < LANCER SPORTBACK > and warning function to warn a person who intends to damage the vehicle*) can be performed by operating the lock/unlock/trunk lid button or panic button on the ignition key (transmitter). Also, WCM incorporates the immobilizer function, which prohibits the starting of engine using an unauthorized key, and the tire pressure monitoring system (TPMS), which issues a warning to a driver by illuminating or flashing the warning light if an abnormality to the tire pressure or system is detected. WCM has the following features
- The ignition key has an indicator light that enables the driver to check if the signal is transmitted correctly or if the battery in the key is discharged.
- Each vehicle is provided with two ignition keys, and up to eight ignition keys can be registered.
- Settings of the keyless entry function can be adjusted using a customization function. NOTE: *: Horn sounds, and headlights and taillights flash.
Scheme 1
Scheme 2
| Parts name | Functional description |
|---|---|
| Wireless control module (WCM) | Controls the keyless entry functions, TPMS functions and starting of the engine by using the following communications. Communications with ETACS-ECU, ECM, ASC-ECU and combination meter via CAN Wire communication with the steering lock unit Wireless communication with the ignition key Wireless communication with the TPMS transmitter |
| Ignition key | The ignition key receives signals sent from WCM, certifies the key ID, calculates the key ID, and sends the reply data signal to WCM. The ignition key also sends signals to WCM when the lock/unlock/trunk lid < LANCER > button and panic button on it are operated. |
| Combination meter (Multi information display, TPMS warning light) | Communicates with WCM via CAN. Send ignition switch status. Receives the warning request or warning information from WCM, activates (1) the TPMS warning light. Warning symbol and message is additionally displayed on the Multi information display. |
| ETACS-ECU | Communicates with WCM via CAN. By the door lock/unlock request, trunk lid open request, or panic alarm request from WCM, ETACS-ECU outputs the lock/unlock signal, trunk lid open signal, or panic alarm signal. When the door lock/unlock signal is output, ETACS-ECU flashes or illuminates the turn signal light and dome light to notify that the lock/unlock operation is performed. |
| ASC-ECU | Communicates with WCM via CAN. Sends the vehicle speed data. |
| Engine control module (ECM) | Communication with WCM via CAN. Send atmospheric pressure data. |
| TPMS transmitter | Measure tire pressure directly, then send radio frequency signal to WCM. |
| (1) Illuminates for tire pressure warning or Flashes for about 1 minute and then continuously illuminated for TPMS malfunction warning. | |
| (1) | Illuminates for tire pressure warning or Flashes for about 1 minute and then continuously illuminated for TPMS malfunction warning. |
MAIN COMPONENTS AND FUNCTIONS
Scheme 3
Scheme 4
Note. In case of replacement of WCM, all keyless ID, key ID and tire pressure sensor ID should be re-registered using scan tool MB991958 (M.U.T.-III sub-assembly).
TECHNICAL DESCRIPTION (COMMENT)
If no data (ETACS transmits engine random number data to WCM via the CAN bus lines) is received from the engine control module via the CAN bus lines when the ignition switch is turned to ON position, it is judged as abnormal.
WCM determines that the abnormality is present when no VIN is recorded in it.
- B1A08: WCM determines that the abnormality is present when the rolling code received from the transmitter 1 (the first transmitter registered in WCM) greatly differs from the rolling code stored in WCM.
- B1A09: WCM determines that the abnormality is present when the rolling code received from the transmitter 2 (the second transmitter registered in WCM) greatly differs from the rolling code stored in WCM.
- B1A0A: WCM determines that the abnormality is present when the rolling code received from the transmitter 3 (the third transmitter registered in WCM) greatly differs from the rolling code stored in WCM.
- B1A0B: WCM determines that the abnormality is present when the rolling code received from the transmitter 4 (the fourth transmitter registered in WCM) greatly differs from the rolling code stored in WCM.
- B1A0C: WCM determines that the abnormality is present when the rolling code received from the transmitter 5 (the fifth transmitter registered in WCM) greatly differs from the rolling code stored in WCM.
- B1A0D: WCM determines that the abnormality is present when the rolling code received from the transmitter 6 (the sixth transmitter registered in WCM) greatly differs from the rolling code stored in WCM.
- B1A0E: WCM determines that the abnormality is present when the rolling code received from the transmitter 7 (the seventh transmitter registered in WCM) greatly differs from the rolling code stored in WCM.
- B1A0F: WCM determines that the abnormality is present when the rolling code received from the transmitter 8 (the eighth transmitter registered in WCM) greatly differs from the rolling code stored in WCM.
- B1A10: WCM determines that the abnormality is present when it receives low battery voltage signal 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 signal 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 signal 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 signal 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 signal 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 signal 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 signal 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 signal from the transmitter 8 (the eighth transmitter registered in WCM) five consecutive times.
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.
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.
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 completed.
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.
WCM determines that the abnormality is present, if it has detected discrepancy in the ignition switch level shown below ten consecutive times when WCM has received the CAN message (ignition switch position information) from ETACS-ECU with the ignition switch turned to the ON or START position.
WCM determines that the abnormality is present when the vehicle information registered in it does not match the vehicle information data.
WCM determines that the abnormality is present when VIN registered in it and the one that has been transmitted on the CAN bus do not match.
When the ignition switch is turned ON, WCM transmits signal to the antenna. When the antenna is found faulty, WCM determines that the abnormality is present.
If the number of keyless ID registered transmitter is zero, the WCM determines that there is a problem.
WCM determines that the abnormality is present, if the data abnormality is found when the ignition switch is turned ON and then EEPROM is written.
If WCM cannot perform the data transmission in normal conditions due to a malfunction of the CAN-B bus circuit, WCM determines that there is a problem.
CIRCUIT OPERATION
WCM receives the vehicle information stored in the ETACS-ECU via CAN bus lines.
If the M.U.T.-III cannot communicate with the WCM, the CAN bus lines may be defective. If the WCM does not work, the WCM or the power supply circuit may be defective.
If only some ignition keys cannot be registered, the ignition key itself may be faulty. If no ignition key can be registered, the key assembly may have already been registered for another vehicle, or the WCM may be faulty.
If the fuel injection does not work, WCM and the MFI system may have a problem. This symptom is not considered abnormal when the engine is started by an ignition key that has not been registered.
If the WCM does not work at all or if the WCM cannot communicate with the scan tool, the WCM power supply or the ground circuit may be defective.
The lock/unlock signals from the transmitter are received by WCM, and then sent to ETACS-ECU from WCM. When ETACS-ECU receives signals from the key reminder switch and all the door switches, ETACS-ECU actuates the keyless entry system.
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.
If the timer lock function does not work normally, the keyless entry transmitter input signal circuit or ETACS-ECU may be faulty.
WCM receives the trunk signal from the transmitter, and sends the signal to ETACS-ECU.