my door locks dont always work when i use my entry button
door locks on 2004 Hyundai Elantra
I have door lock issues too!
If you mean the entry button on the remote control, the battery in it may be going dead and in need of replacement. Once the remote is apart to change the battery check the connections and contacts with in the remote are clean and secure. Hyundai have a factory website with lots of free technical information check it out