Try turning the latch mechanism by hand before closing the door.
Inspect the latch visually for any break or damaged.
On most of the cars open - close door systems latch/hatch are used.
If the Latch looks stiff and very dried up,then try spraying it with few oil drops to make the latch movement free.
If the latch looks very dull and loose then either its time to replace the latch or else its fitting assembly needs to be inspected and realigned.
On some car models the latch moves automatically and get open/close and on some car models its controlled by spring assembly.Inspect that assembly.
UNDERSTAND THE SIMPLE THEORY OF VEHICLES DOOR LATCH:----
Latch contains locking device.
These allows user to lock the latch.
On opposite side of the latch there is a part called striker.
The latch rests there on striker when the door is closed.
The latch is held in the assembly by a part called clasp.
So when door is closed,the latch is locked,at that time its held by clasp and latch rests on striker.
Now when you open the door,clasp will release the latch in open position and striker will open the door.
So all these latch,clasp,striker,their moving assembly needs properly inspected to confirm the problem.
Also make sure that nothing is blocking the latch or its internal support components from its movement.
Sometimes a piece of cloth or dirt/dust gets collected or stuck-up there and these causes the problem.
The latch has to move in and out.The latch is like a clip,it should hold and release when you close and open the door.
if the latch is not giving any movement while you open or close the door then it has to be replaced.
If the door is locked and not getting opened,due to stuck up latch,then you have to manually disengage the latch.
The latch moves up to close and down to open.
You can try these move the latch up by hand to close and then pull handel manually to open the latch.
Dont slam the door hard,it will damage the door as well as latch assembly.
These details will help you.
Thanks.
