1.Outline of double locking system
In Europe, making the theft deterrent system satisfactory is essential. This double locking system is one such device to meet British insurance requirements (designated by Thatcham). This device was developed to prevent intrusion into the cabin for two minutes minimum. The double locking system is a door lock mechanism with a dedicated link mechanism. If the doors are locked with the lock switch of the wireless door lock transmitter, the door cannot be unlocked even when the door lock knob is operated from the cabin. Owing to this mechanism, even if the window glass is broken and the door lock knob is operated, the door cannot be opened making it difficult to intrude into the vehicle. Setting/unsetting of the door locking system is as follows.
(1)Double locking set
To lock the doors with this system, pressing the transmitter’s door lock switch, then pressing it again within five seconds activates the double locking system.
Double locking set is performed only when the second lock signal is received within 5 seconds after receiving the first lock signal from the transmitter. If the second lock signal is received after five seconds or more from the first lock signal, only the normal operation is performed. Also, after that point, even if two lock signals are received within five seconds, double lock set is not performed. In this case, it is necessary to perform double locking set after performing unlock operation by the transmitter.
(2)Double locking unset
One unlock operation of the transmitter unsets the double lock and unlocks the door at the same time.
In case the double lock cannot be unlocked by the transmitter, such as when the battery is dead, only the driver’s door can be unlocked with a key mechanically. When the key is inserted into the ignition key cylinder, if any one door is in double locked condition, the double lock is unset (return to the normal lock). After turning the ignition switch from LOCK to ON and until the driver’s door is opened, double locking set is invalidated.
2.Location of components
The double locking system consists of the following components.
(1)Door lock assembly
(Double locking actuator)
(3)Key unlock warning switch
(4)Door courtesy switch
(5)Door lock control switch
(Power window master switch)
(6)Door control receiver
(7)Body ECU or integration relay
(8)Double lock ECU
3.Construction of double locking actuator
(1)The double locking actuator is built in the door lock assembly.
(2)The actuator contains both the mechanism for the door lock system and the double locking system including motors and links.
(3)The functions of the components of the double locking actuator.
An input/output lever connected directly to the door lock knob.
A lever that connects the knob lever and the mechanical lever.
Double locking lever
A lever that engages and disengages the link lever.
A lever that operates the door locking portion.
Double locking motor
A motor that sets double lock and releases double lock by moving the double locking lever.
Door lock motor
A motor that locks and unlocks normally by moving the mechanical lever.
(1)When a door is locked through the operation of the transmitter, it locks in the normal manner.
The knob lever becomes disengaged by the function of the double locking motor. As a result, if an attempt is made to unlock the door by operating the door lock knob, the knob lever will merely mis-swing, without being able to unlock the door.
(2)The locking/unlocking function of the double locking system is normally activated by operating the transmitter.
1.Outline of double locking system