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 fix it. First, ensure that it's not your backup remote.
If the backup remote is able to lock and unlock your car doors then there is likely an issue with the primary remote. The majority of car remote key malfunctions are caused by battery or circuitry problems.
Battery
It is not unusual for the battery in the car key fob to wear out. It is relatively easy to replace the battery, however it is essential to ensure that you use the right type that you can refer to the owner's manual or talk to the manufacturer's dealer to find out what kind of battery you require. It is also a good idea to examine the battery compartment with care since dead batteries may leak caustic chemicals that can harm the remote. If replacing the battery does not solve the issue, there may be other issues requiring professional attention. For example, if buttons appear stuck or damaged It may be necessary to take the remote apart and rework its parts. You can also try reprogramming the vehicle to recognize the new key fob.
Buttons
From frequent use, key fobs can wear out and become dirty. This is not unusual however, it can cause buttons to cease working or require a hard press for them to work. This can be a hassle especially when you're away from home and you need to switch on your car. Fortunately, even worn-out or malfunctioning buttons can often be fixed with a little time and a few items you may already have around the house.
First, check that the batteries are properly charged and that the indentation on the back of the button is filled. Then, carefully open the remote and examine the circuit board. Examine for evidence of rust, or other indications that the buttons have been damaged or worn. For example there could be conductive paint missing. Use a Q-tip, dipped in rubbing alcohol to gently clean any membrane contact that has become worn out or has conductive paint missing. Avoid rubbing too hard since this could cause damage to the conductive paint and block the button from firing when it is the button is pressed.
Check the battery connector's terminals carefully for any loose solder connections. If this is the case, reconnecting them can restore functionality to the button. The same procedure can be used to restore function to any other loose connections within the fob.
If, for instance, any of the buttons made of rubber that are on the front of the key fob stop working or require a very long press to function it is likely the graphite disks that are on the back of the button are wearing out and need to be replaced. This can usually be done by rubbing a pencil on the disks, which will bring the button back to life.
If none of this is useful, or if the button does not respond to a hard push It could be that the circuit board itself has become damaged. This can sometimes be repaired by a quick clean, and re-soldering, but it is best to have an extra fob on hand in the event that this method does not work for you.
Circuitry
If the keys fob buttons are functioning the circuit board in your remote might be dirty. A thorough examination is often enough to resolve this issue. Water and broken cases are the most common causes of dirty boards. A damaged case allows water and other debris to enter and short out the electronic components. Water can also damage pins and connectors on the board, referred to as via's.
If you are handy enough to open your key fob and don't mind making a mess, we can take the buttons out of their sockets and then solder new ones. Also, you should check the connections between battery terminals. car key fob repair service can become very filthy and if they're not tight enough, the buttons might not function or may even remain in their down position. Soldering the terminals back to their original positions is often enough to restore a non-working fob back to working.
Non-Remote Transponder Chips
The non-remote chips that are sealed are more durable than remote fobs. However, they are susceptible to breaking when a hole is made in them, or when a door handle for a car or lawnmowers is pushed over them. Most of the time, non-remote transponder chips fail, and this can be blamed on a blown fuse.
If you're able to open up a key fob that is sealed and can tolerate the mess, you can remove the circuit board and check the fuse with a multimeter for proper diode function. If you're not comfortable with this, you can visit your local Oreilly or hardware store and utilize their RF frequency tester. This will tell you whether the key fob sends signals.
Programming
Key fobs endure a lot of abuse and aren't indestructible. They may lose their connection to the receiver in your car due to shock or low battery, which calls for them to be reprogrammed. A professional auto locksmith or dealer can reprogram your key fob to get it working again. If resetting or repairing your key fob fails it is possible to replace it.