How to Fix a Key Fob That isn't Working
If your key fob isn't functioning There are a few simple steps that can be taken to fix it. First, check to make sure it's not the backup remote.
If the backup can lock and unlock your car doors it is most likely an issue with the primary remote. The most frequent causes of key malfunctions for car remotes are circuitry or battery issues.
Battery
The battery in the key fob may wear out over time. It is relatively easy to replace a battery, although it is crucial to ensure you choose the correct type and you can consult your owner's manual, or contact the dealer of the manufacturer to find out what kind of battery you require. It is recommended to examine the battery compartment thoroughly since dead batteries may leak harmful chemicals that can harm the remote. If replacing the batteries doesn't solve the issue, it may be that there are other issues that require attention from a professional. If the buttons are stuck or broken for instance it could be necessary to disassemble the remote and rework each component. You could also try reprogramming the vehicle to recognize the new remote.
Buttons
Key fobs can get filthy and worn out due to frequent use. It is not unusual for buttons to stop functioning, or require a hefty press to get them working. This can be very frustrating especially if you're out of town and need to start your vehicle. Fortunately, even worn out or damaged buttons can be fixed with just a bit of time and some of the materials you might already have in the home.
First, check that the batteries are up correctly and that the indentation on the back of the button is filled. Then, carefully remove the remote and inspect the circuit board. Examine for signs of rust or other signs that buttons are worn out or damaged, like missing the conductive paint. Utilizing a Q-tip dipped in alcohol, gently clean any membrane contacts that have worn or have conductive paint missing. Don't rub too hard, as this could erode the conductive paint and stop the button from firing when you press it.
Also, make sure to inspect the battery connector's terminals for any loose solder connections. Soldering them back to their original position will restore the button's functionality in the event that this is the situation. You can apply the same process to restore functionality to any other loose connection in the fob.
If broken car key repair of the rubber buttons located at the front of the keyfob aren't working or require being pressed extremely hard, the graphite disks at the back of the button could have worn out and will need to replaced. This can usually be done by rubbing a pencil across the disks, which should bring the button back to its original state.
If none of this is helpful, or if the button still doesn't respond to a hard press, then it may be that the circuit board is damaged. It is possible to fix this issue by cleaning and re-soldering the fob but you should also have an extra in case it does not work.
Circuitry
The circuit board in the remote control could be dirty regardless of whether the buttons on the key fob function or not. This issue can be fixed through a thorough examination. The most common causes for dirty circuit boards is water and broken cases. A damaged case allows water and other debris to get in and short out the electronic components. Water can also get through pins and vias, which are tiny connectors that are found on the board.
If you're handy enough to open your key fob and aren't afraid of making a mess, we can remove the solder from the buttons and then solder new ones in their place. Also, you should check the connections between the battery terminals. They can get very filthy and if they're not tight enough, the buttons might not work or even stick in their down position. Soldering the terminals and button's back into place is typically all that's required to return the key fob that is not working to functioning condition.
Non-Remote transponder chips
The non-remote chips sealed in a sealed case are more durable than remote fobs, but they are susceptible to breaking when a hole is made into them or if a car door handle or lawnmower runs over them. The majority of non-remote transponder chip failures can be blamed on an exploded fuse.
If you're able to remove a key fob that is sealed and are willing to put up with the mess, you can remove the circuit board and check the fuse using a multimeter for proper diode function. If you're not confident doing this, visit your local hardware store or Oreilly's and they will usually have an RF frequency tester that will tell you whether the key fob is sending signals.
Programming
Key fobs aren't indestructible and can be damaged by a lot of things. They can lose their pairing to the car's receiver because of shock or a low battery, which requires the reprogramming. A professional auto locksmith or a dealer in the main, can reprogram your keyfob and get it up and running again. If resetting or fixing the keyfob is not working it is possible to replace it.