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System Overview






System overview

System overview





Note! This document describes the central locking system in cars with a keyless vehicle module (KVM). Some components are different from the standard central locking system. This document outlines the main functionality of the central locking system with keyless entry. For more detailed information about the keyless entry system, see Design and Function, keyless vehicle module (KVM).

The central locking system contains a number of functions. The system is monitored by the central electronic module (CEM). The central electronic module (CEM) communicates with the constituent units, whether directly connected or connected in series, via the CAN network.

The functions covered are:
- standard locking function (total or 2 stage)
- deadlocked (not USA/CDN)
- private locking mode
- electrical child-proof lock (option)
- unlocking the trunk lid/tailgate
- unlocking the fuel tank filler cover
- light functions (local lighting and approach lights)
- indication of the status of the doors and hatches
- remote unlocking (option)
- Automatic locking when driving
- re-locking
- passive functions.

Standard locking function
The standard locking function unlocks the side doors and activates the switch so that the tailgate/trunk lid can be opened when the switch is pressed in. Unlocking and locking occur normally using the button on the remote key. There are two settings for the central locking system:
- total
- 2 stage.
Total unlocking unlocks all doors at the same time. The American market has 2 stage unlocking as standard, which unlocks the vehicle in two stages. The first time the unlock button is pressed on the remote key, the driver's door unlocks. If the button is pressed again within 10 seconds, the other doors are unlocked. When unlocking a 2 stage system with the key, the key must be turned counter-clockwise twice for all doors to unlock.
When depressing the lock button on the remote control, all the doors lock and the switch on the tailgate/trunk lid deactivates.
The type of locking that is to be active can be selected via the menu in the infotainment control module (ICM).

Deadlocked (not USA/CAN)
Deadlocking is an option. Deadlocking means that the inner door handles and central locking switch are disengaged when the central locking is locked. It will not then be possible to open a side door from the inside, even if a window is smashed. Deadlocking is activated 10 seconds after the vehicle was locked. This function requires lock units with lock motors for this function. The function can be temporarily disengaged using the switch for reduced alarm.

Valet locking mode
The glove compartment and cargo compartment can be locked in "valet" mode. This function is used to block access to the Glove compartment and cargo compartment when, for example, leaving the car for a service when there are personal belongings left in the car.

Electrical child-proof lock (option)
Child-proof locking disengages the rear internal door handles. The switch is on the control panel in the driver's door. The rear window lift mechanisms cannot be operated either when the function is activated.
There are standard mechanical controls that can be affected if you do not wish the rear doors to be able to be opened from inside at all.

Unlocking the trunk lid/tailgate
In practice there is no "locked" mode for the lock on the tailgate/trunk lid. The difference between locked and unlocked is whether the central electronic module (CEM) will activate the lock motor or not when the switch on the tailgate/trunk lid is pressed.
The tailgate/trunk lid can also be unlocked from inside the vehicle using a switch on the light switch module (LSM).
The tailgate/trunk lid is "locked" and "unlocked" at the same time as other doors if an unlock command is received from the remote key. The tailgate/trunk lid can also be unlocked separately using a dedicated button on the remote key.
As a standby option the tailgate can also be opened using the key blade. In order to do this, the protective cover next to the switch on the tailgate must be removed to expose the lock cylinder. The remedy will deploy the alarm if installed. The alarm can be reset by inserting the remote key in the starter module.
The switch on the tailgate or trunk lid is directly connected to the keyless vehicle module (KVM) and to the central electronic module (CEM). The lock motor is directly connected to the central electronic module (CEM).

Unlocking the fuel tank filler cover
The opening switch for the fuel tank filler cover is on the light switch module (LSM) to the left of the driver. The light switch module (LSM) is serially connected to the central electronic module (CEM) via LIN. The lock motor for the fuel tank filler cover is at the rear edge of the fuel tank filler cover. The lock motor is directly connected to the central electronic module (CEM).

Light functions
Local lighting and approach lights are part of the system.
Local lighting is activated using the remote key. Approach lights are activated when the high/low beam switch is pulled backwards when the vehicle is parked.

Door, lock and lid switches
There are contact breakers on the side doors and tailgate/trunk lid which indicate whether the door or lid is open or closed. There is also a separate contact breaker at the hood if the car has an alarm. There is no contact breaker at the fuel tank filler cover. The contact breakers are closed when the door or lid is closed, providing a ground connection to the central electronic module (CEM).
There is a contact breaker in each lock unit that indicates the position of the lock motors on the central locking motor and lock motor for electrical child-proof lock (if such a lock unit is installed). The contact breakers are directly connected to its respective door control module, which then forwards the information to the central electronic module (CEM).

Automatic locking when driving
The system can be activated so that the car is locked automatically when the car reaches 7 km/h (5 mph). Whether this function is activated on delivery or not depends on the market. This function can be activated or deactivated via a menu in the infotainment control module (ICM).

Re-locking
The system has a function for re-locking. If the car is unlocked using the remote key or key blade and the side doors or trunk lid/tailgate are not opened within 2 minutes, the car will be locked automatically. This function prevents the car from being left unlocked unintentionally.

Passive functions
The passive functions are controlled by the keyless vehicle module (KVM). These passive functions cover unlocking, locking and vehicle start. To this end, certain components are connected to the keyless vehicle module (KVM) instead of the central electronic module (CEM). For more detailed information about the passive functions, see Design and Function, keyless vehicle module (KVM).

Text message for the lock system
The text message window in the driver information module (DIM) indicates whether child-proof locking, valet locking or reduced alarm is activated. There is also an alert message if a door opens whilst driving.

Customer settings
The customer can make certain settings to determine how the locking system works. For more information, see: Diagnostic functions Diagnostic Functions

Acknowledgements
The turn signal lamps give a long flash to confirm that the car is fully locked. They flash twice when the car is unlocked. The customer can decide whether the acknowledgement is activated or not via the menu system in the infotainment control module (ICM).

Remote key
The central locking system can be unlocked using the remote key.

The remote key has buttons for:
- unlocking
- locking
- unlocking the trunk lid/tailgate
- panic function
- approach lighting
- activating status control of the central locking and heartbeat sensor
The remote key also supports keyless functionality where applicable. This means that there is an additional communication circuit in the remote key compared to a "standard" remote key. The remote keys for keyless functionality also have several buttons.

Panic function
The panic function can be activated using the remote key. The panic function activates the horn for 30 seconds. This function is to attract attention in an emergency situation.

Unlocking using the key blade
The driver's door can be locked and unlocked using the key blade which is normally retracted inside the remote key. This is an extra solution should there be a fault in the system. The other doors can be unlocked using the inner central locking buttons after the remote key is inserted in the starter module. The remedy will deploy the alarm if installed. The alarm can be reset by inserting the remote key in the starter module. On vehicles with keyless functionality, the lock cylinder is covered by a cover. This cover must first be removed to expose the lock cylinder. This is done by inserting the mechanical key in a hole on the underneath of the cover and pulling out.

Remote unlocking (option)
Volvo On Call can be used to unlock the vehicle from a Volvo Service Center if the customer is unable to open the vehicle in the normal way for any reason. For further information about Volvo On Call, see Design and Function, phone module (PHM).