Problems with centralized closure

Hello, I have a kia shuma of the year 2000 and lately I was giving problems the central locking since it works when you want, and observing it I have realized that it works while I have the contact given, or if I do not work either the key, or closing it manually from the inside, to see if someone can give me a clue where I have to put a hand since the economy does not go very buoyant, thank you very much.

First of all check the fuses and wiring there may be some false contact, make proven whether or not the other door, test and warn me

Hello thanks for answering, I tell you only the closure with the driver's door and with no other, now when I have lowered to park it well, because where I live you have to park it where you can, it has worked well as if nothing had happened,

Ok then your car has only the activator at the driver's door, take the test with the door open to see if it works well, if so it was some problem of the centralized closure switch