The central locking switch is located next to the driver's seat in the car. When the driver presses this switch, they can control the door locks of the other three doors. Conversely, each car door can be controlled independently. A common malfunction of the central lock as a control device is that it becomes unresponsive, causing the doors not to lock. If all four door locks can only be opened, it indicates that there's a fault in the central lock actuator.
There are many different products related to the car's central locking system, but the basic components primarily include the door lock switch, the door lock actuator, and the door lock controller. A malfunctioning central lock is the reason why a car door can't be locked. Typically, it's the door lock actuator and the door lock controller that malfunction.
When there's a malfunction in the door lock, the door latch mechanism changes, preventing the car door from closing. When disassembling the car door lock, it's necessary to remove the lock's control device and the securing clip between the control device and its fitting. After installing a new lock, it's essential to repeatedly adjust until the car door can open and close normally.
A faulty door handle can also prevent the car door from closing. The cause is often an issue with the pull wire of the door handle. If the pull wire is not positioned correctly, opening and closing the door may become strenuous, and it may not even close. A simple adjustment to the pull wire can solve this. Additionally, excessive friction between the door handle and the lock pillar, due to prolonged use, can lead to poor lubrication when opening and closing. In severe cases, this could prevent the entire car door from closing. In such situations, it's helpful to add some lubricant to the door lock.
