Page 334 - 05. Subyek Teknik Mesin - Automobile Mechanical and Electrical Systems Automotive Technology Vehicle Maintenance and Repair (Vehicle Maintenance Repr Nv2) by Tom Denton

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316 Automobile mechanical and electrical systems

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Figure 3.119 Sunroof circuit: 1, motor; 2, micro-switch

Figure 3.120 Remote door locking

3.4.5.4 Locking
When the key is turned in the driver’s door lock (or the remote button is pressed),
all the other doors on the vehicle should also lock ( Fig. 3.120 ). Motors or
solenoids in each door achieve this. If the system can only be operated from the
driver’s door key, then an actuator is not required in this door. If the system can
be operated from either front door or by remote control then all the doors need
an actuator. Vehicles with built-in alarm systems lock all the doors as the alarm
is set.
A simplifi ed door locking circuit is shown in Fig. 3.121 . The main control unit
contains two change-over relays (reverse circuit), which are actuated by either
the door lock switch or, if fi tted, the remote key. The motors for each door lock
are wired in parallel and all operate at the same time. Most door actuators are
small motors or solenoids.

Remote-control central door locking is controlled by a small hand-held
transmitter and a sensor receiver unit. When the key is operated, by pressing
a small switch, a complex code is transmitted. Trillions of different code
combinations are used in modern systems. The sensor in the car picks up this