How to Repair a Car Key Fob

Check your remote to see whether it is held together by a small Philips-head screw. If so, remove it. Look at the join seam that runs along the middle of your remote. Search for a small indentation in which your miniature flathead screwdriver can be inserted. If not, use the seam itself, and gently pry it apart with your flathead screwdriver.

Spray the inside of the remote with canned air to remove any debris. Remove the battery, and dispose of it unless it is relatively new. It should be replaced when you re-assemble the fob.

Remove the button pad from the top of the remote, and using the alcohol with cotton swabs, clean around the buttons and the plastic frame it fits in to make sure it's clean. Lay it aside for it to dry.

Remove the remote's interior circuit board. Generally, the problem with remotes is that the contacts have worn thin and have ceased to make a proper electrical contact with the rest of the remote. These contacts are usually gold in color. Clean these with the cotton swabs and alcohol. Reassemble your fob, and check to see whether it works.

Reopen the fob if the clean contacts did not make a difference. To rebuild the contact surface, do one of several things: First, use a tiny bit of metallic paint applied gingerly with a paint brush or build up the contact surface by rubbing it with a pencil. Another solution is to use conductive coating, which is available at electronic shops. Let it dry 12 hours before re-assembling the fob and checking to see if it works.

Replace your battery, and close your key fob by pressing the two halves back together. It should click back into place. Replace any screws removed upon disassembly.