How to Fix a Key Fob That isn't Working
If your key fob does not work, you can fix it with just a few steps. The first step is to be sure that it's not your backup remote.
If the backup can lock and unlock your car doors, then there's a likely issue with the primary remote. Most car remote key failures are caused by circuitry or battery problems.
Battery
The battery in the key fob could get worn out over the course of time. It is relatively easy to replace a battery, although it is crucial to ensure you choose the correct type; you can look in the owner's manual or talk to the manufacturer's dealer to find out the kind of battery you need. It's recommended to examine the battery compartment carefully because dead batteries can leak harmful chemicals that can damage the remote. If changing the battery doesn't fix the problem there could be other issues requiring professional attention. If the buttons are damaged or stuck for instance it could be necessary to disassemble the remote and rework each component. It is also possible to reprogramme the vehicle to recognize the new remote.
car key repair service may become dirty and worn-out from repeated use. This is not atypical however it can cause buttons to cease working or require a long press to function. This can be very frustrating especially when you're away from your home and you need to start your car. Even worn-out or malfunctioning buttons can be fixed with a bit of time and tools you already have at home.
First, check that the batteries are up correctly and that the indentation on the back of the button is filled. Take the remote apart and examine 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 a Q-tip that has been dipped in alcohol to gently clean any membrane contacts that have worn or have conductive paint missing. Don't rub too hard in order to damage the conductive paint and prevent the button from firing when you press it.
Also, make sure to inspect the battery connector's terminals to ensure any loose solder connections. If this is the case, soldering them back in place can restore function to the button. The same procedure can be used to restore functionality to any other loose connections in the fob.
In the end, if any of the buttons made of rubber that are on the front of the key fob have stopped functioning or require a long press to function it is likely the graphite disks that are on the back of the button are wearing down and require replacement. It is usually done by rubbing a pen over 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 pressed hard, it could be that the circuitry is failing. This can be fixed by a quick clean, and re-soldering, but it is ideal to have a spare fob in case this method fails for you.
Circuitry
The circuit board of your remote control may be dirty regardless of whether the buttons on the key fob work or not. The issue can be solved by a thorough inspection. The most common causes for dirty circuit boards are water and broken cases. A damaged case could allow water and other debris to get into the circuit board, causing it to short. Water can also get through pins and vias, which are the tiny connectors that are found on the board.
If you are handy enough to open your key fob, and aren't afraid of making some 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 may not work or even stay in their down position. Soldering the terminals and button's back in place is usually all it takes to restore a non-working key fob to functioning condition.
Non-Remote Transponder Chips
Sealed non-remote transponder chips are much more durable than the remote fobs that contain them however they are still susceptible to being cracked by a hole made in them or pushed over by a lawnmowers blade or car door handle. Failures of the fuse are typically to blame for non-remote chip failures.
If you're not confident opening the key fob, you can remove the circuitboard and use a multimeter to verify that the diode is working properly. If you're not comfortable with this, visit your local Oreilly or hardware store and test their RF frequency tester. This will let you know whether the key fob sends an RF signal.
Programming
Key fobs endure a lot of abuse and aren't indestructible. They can lose their pairing to the receiver in your car because of shock or a low battery, requiring the reprogramming. A professional auto locksmith or a main dealer can reprogram your key fob to get it functioning again. If resetting or replacing your keyfob does not work, you may need to replace it.