How to Fix a Key Fob That isn't Working

If your key fob doesn't work, a few easy steps can be taken to fix it. First, check to make sure it's not the backup remote.

If your backup remote cannot lock and unlock the doors of your vehicle, it is likely that the main remote is not working. Most problems with car remote keys result from battery or circuitry problems.

Battery

The battery inside the key fob could get worn out over the course of time. It is fairly easy to change out a battery, although it is crucial to make sure that you select the correct one; you can look in your owner's manual or contact the manufacturer's dealer to find out the kind of battery you require. It is also crucial to inspect the battery compartment, as batteries that are not working properly can release caustic chemicals which can damage the remote. If changing the battery doesn't fix the issue there could be other issues that require attention from a professional. If the buttons are broken or stuck, for example, it may be necessary take the remote apart and rework each component. You could also try reprogramming the vehicle to recognize the new remote.

Buttons

Key fobs may become dirty and worn out from repeated use. It is not common to have buttons stop functioning, or require a hefty press to get them working. This can be very frustrating, especially if you are out of town and need to start your car. Even malfunctioning or worn-out buttons can be fixed with a little time and the tools you already have at home.

First, make sure the batteries are up correctly and that the indentation on the back of the button is filled. Take the remote apart and keys examine the circuit board. Examine for signs of rust or other indications that buttons are worn out or damaged, like missing paint that is conductive. Use a Q-tip dipped into alcohol to gently clean any membrane contact that has become worn out or has conductive paint missing. Do not rub too vigorously as this can damage the conductive paint and stop the button from firing when it is pressed.

Check the battery connector's terminals for loose solder connections. Soldering them back into place will restore the button's functionality in the event that this is the case. You can follow the same method to restore functionality to any other loose connection within the fob.

If any of the rubber buttons on the front of the keyfob aren't working or need to be press extremely hard, the graphite disks at the back of the button might have worn out and will need to replaced. This is usually done by rubbing a pencil over the disks, which will bring the button back to its original state.

If none of these solutions work or you not be able to get the button respond when pressed hard, it could be that the circuitry is failing. It is possible to fix this issue by cleaning and re-soldering the fob but you should also have an extra in case it doesn't work.

Circuitry

If the keys fob buttons are functioning the circuit board that is inside your remote might be dirty. A thorough inspection will usually resolve this problem. The most common causes for dirty circuit boards are water and broken cases. A damaged case can let water and other debris to enter the circuit board, which can cause it to short. Water can also eat away at pins and small connectors on the board called via's.

If you're able to open up your key fob and aren't afraid of making a mess, we can take off the buttons and put new ones in their place. It's also worth looking at the battery terminal connections. If they're loose, the buttons might not function properly or become stuck in their down position. Soldering the terminals and buttons back in place is usually all that's needed to return keys that are not in working condition.

Non-Remote transponder chips

Sealed non-remote transponder chips are much more durable than remote fobs that contain them but they can be damaged by a hole that is drilled into them or run over by a lawnmower or car door handle. The failure of the fuse is usually to blame for non-remote chips failures.

If you're not comfortable opening the key fob, you may take the circuit board off and use a multimeter to verify that the diode is working properly. If you're not sure with this, go to your local Oreilly or hardware store and test their RF frequency tester. This will inform you whether the key fob is sending a signal.

Programming

Key fobs endure many abuses and aren't impervious to damage. They may lose their connection with the receiver in your vehicle due to shocks or a low-battery, which requires the reprogramming. A professional auto locksmith or a main dealer will be able to reprogram your key fob repair service fob to get it back up and running. If, in the unlikely event that resetting or repairing your key fob isn't working it could be the time to replace it all over again.