How to Fix a Key Fob That isn't Working
If your key fob doesn't work, a few easy steps can fix it. First, ensure that it's not your backup remote.
If the backup can lock and unlock your car doors, it is most likely an issue with the main remote. The most frequent causes of car remote key failure are battery or circuitry issues.
Battery
It is not uncommon for the battery inside a key fob for cars to get worn out. It is simple to replace a battery. However it is essential to select the right kind. You can check your owner's manual or call the manufacturer to find out the right type. It's also a good idea to examine the battery compartment carefully because dead batteries can leak caustic chemicals that can cause damage to the remote. If replacing the battery does not solve the issue there could be other issues that require professional attention. If the buttons are broken or stuck for instance it might be necessary to take the remote apart and rework each component. You could also try reprogramming the vehicle to recognize the new device.
Buttons
Key fobs may become dirty and worn-out from frequent use. It is not unusual for buttons to cease working, or to require a hard push to make them work. This can be frustrating particularly when you're away from your home and need to start your car. Fortunately, even worn out or malfunctioning buttons can often be fixed with just a bit of time and a few items you have in the home.
First, check that the batteries are charged correctly and that the indentation on the back of the button is filled. Then, carefully remove the remote and look at the circuit board. Look for signs of corrosion or other signs that the buttons are worn out or damaged, such as missing paint that is conductive. Utilizing the Q-tip, dipped in rubbing alcohol, gently clean any membrane contacts that have damaged or where conductive paint is missing. Be careful not to rub too hard, as this can erode the conductive paint and stop the button firing when pressed.
Examine the battery connector's terminals carefully for any loose solder connections. If this is the case, simply soldering them back in place can bring back function to the button. You can follow the same procedure to restore functionality to any other loose connection in the fob.
If any of the rubber buttons on the front of the keyfob aren't working or require being pressed very hard, the graphite disks at the back of the button may have worn out and require replacement. key car repair is usually done by rubbing a pen across the disks. This will bring the button back to life.
If none of these solutions work, or if you still cannot get the button to respond when you press it hard, it is possible that the circuitry is failing. It is possible to fix this by a quick clean, and re-soldering, but it is ideal to have a spare fob available in the event this method does not work for you.
Circuitry
Whether or not the key fob buttons are working the circuit board that is inside your remote may be dirty. This problem can be resolved by a thorough inspection. Broken and damaged cases are the most common causes of boards that are dirty. A broken case allows water and other debris to enter and short out the electronics. Water can also get through pins and vias, which are small connectors on the board.
If you're able to open your key fob, and you don't mind making a mess, we can take the buttons out of their sockets and solder in new ones. It's also worth checking the battery terminal connections. They can become extremely dirty and if they're loose, the buttons might not function or even stick in their down position. Soldering terminals and buttons back to their original positions is often enough to restore a non-working fob to a working condition.
Non-Remote transponder chips
Sealed non-remote transponder chips are much more durable than remote fobs they are contained in, however they are still susceptible to being broken by a hole being made in them or pushed over by a lawnmowers blade or car door handle. Most of the time non-remote transponder chip failures can be attributed to blowing fuses.
If you are not comfortable opening the key fob, you can take the circuit board off and use a multimeter to check that the diode is functioning correctly. If you're not comfortable doing this, visit your local hardware store or the Oreilly's and they usually have an RF frequency tester that will determine whether the key fob is sending a signal.
Programming
Key fobs endure many abuses and aren't indestructible. They may lose their connection with the receiver inside your vehicle due to shocks or low-battery, which requires changing the program. A professional auto locksmith or a dealer in the main, can reprogram your key fob and get it back working again. If, in the unlikely event that resetting and repairing your key fob fails it could be the time to replace it entirely.