Car door lock

How to detect the door lock failure

To inspect the component, insert the key into the cylinder as far as it can go, then move it there up and down. The free travel of the key indicates the ultimate wear of the lock cylinder pins.

Then you have to open and close the lock a few times. Too easy or too tight key movement indicates the part failure.

Special equipment is required for more comprehensive diagnostics, so it must be performed at a service station.

You may identify that the car door lock has to be inspected by the following symptoms:

• it is impossible to close or open the vehicle door;
• you hear abnormal sounds while driving;
• increased gaps between the body and the doors;
• the lock response requires excessive force.

Causes of the door lock failure

One of the most frequent part failures is wear of the cylinder pins. It is a natural process, which you cannot avoid. But there are reasons for premature abrasion of the mechanism components. Usually they are the component poor quality and the lack of lubricant inside its housing.

Dirt and moisture have a disruptive impact on the mechanism: they promote its corrosion and jamming. So to prevent the premature failure of the lock, it is significant to monitor the spring flap operation, which protects its elements from the adverse environmental impact.

Moisture accumulation inside the component is especially hazardous in cold seasons, because water can freeze at low temperatures. In this case drivers often apply excessive force on the mechanism components, trying to open the door, which may result in the failure of both the lock and the key.

In some cases the cause of the part malfunction lies in usage of unsuitable compounds for servicing it. For instance, the popular anti-corrosion spray WD-40 not only fails to lubricate parts sufficiently, but also washes out the lubricant put into the mechanism by its manufacturer. Besides, kerosene-based products are water-retaining and absorb moisture from the environment.

Repair of the door lock  

The mechanism of vehicle locks is rather complex, so it is best to entrust its repair to specialists. When performing DIY repair it is advisable to replace the core in the assembly. For this you need:

1. Turn the lock cylinder to the position corresponding to the open door.
2. Remove the door trim.
3. Unscrew the bolt attaching the core to the lock.
4. Carefully press the cylinder and remove it from the mechanism housing. If it is stuck in the closed position, you may need a drill to remove the cylinder.
5. Install a new part and check its performance.
6. Reinstall all the parts.

Replacement of the car door lock

You can install new door locks on the vehicle by yourself. For this, do the following:

1. Remove the door trim.
2. Dismantle the inner door handle.
3. Disconnect the linkage from the outer handle, unfastening the plastic clip, and then the linkage going to the lock switch.
4. Unscrew the mechanism to the door panel fasteners and demount it by pulling it out of the seat in the body.
5. Disconnect the linkage coming from the inner and outer handles, as well as the locking rod from the lock.
6. Unscrew the latch fasteners to the body pillar.
7. Install new parts in the order reverse to removal.