How to Fix a Key Fob That isn't Working
If your key fob does not work and you're not sure why, you can fix it by following some simple steps. First, make sure that it's not your backup remote.
If the backup is able to lock and unlock your car door, then there's a likely issue with the main remote. Most car remote key failures are caused by circuitry or battery problems.
Battery
The battery inside a key fob can get worn out over the course of time. It is easy to replace batteries. However it is essential that you use the correct type. You can consult your owner's manual or call the manufacturer to inquire about the correct type. It is also essential to inspect the battery compartment, since dead batteries can leak caustic chemicals that can harm the remote. If changing the batteries doesn't solve the issue it could be that there are other issues that require attention from a professional. If the buttons are broken or stuck, for example it could be necessary to remove the remote and rebuild each component. You can also try reprogramming the vehicle to recognize the new device.
Buttons
Key fobs can become filthy and worn out due to repeated use. It is not unusual for buttons to cease working, or to require a hard push to make them work. This can be a hassle particularly when you're away from your home and have to turn on your car. Even malfunctioning or worn-out buttons can be fixed with a bit of time and the tools you already have at home.
First, ensure 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. Look for signs of corrosion or other signs that the buttons are worn out or damaged, such as missing paint that is conductive. Then, using the Q-tip, dipped in alcohol to gently clean any membrane contacts that have worn or have conductive paint missing. Avoid rubbing too hard as this can erode the conductive painting and prevent the button from firing when it is it is pressed.
Examine the battery connector's terminals carefully for any loose solder connections. Soldering them back into place can restore the button's functionality If this is the situation. The same process can be used to restore function to any loose connections in the fob.
If any of the rubber buttons on the front of the keyfob isn't working or require being pressed extremely hard the graphite disks on the back of the button may have worn out and require replacement. This can usually be done by rubbing a pencil over the disks, which should bring the button back to life.
If none of this is useful, or if the button still does not respond to a hard press It could be that the circuit board itself has become damaged. This can be fixed with a quick clean and re-soldering, but it is ideal to have a spare fob on hand in the event that this method doesn't work for you.
Circuitry
The circuit board of your remote control could be dirty regardless of whether the buttons on the key fob work or not. The issue can be solved through a thorough examination. The most frequent causes of dirty circuit boards are water and broken cases. A broken case allows water and other debris to pass through and short circuit the electronic components. Water can also destroy pins and connectors on the board called via's.
If you're able 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. Also, key car repair checking the connections between the battery terminals. They can become very filthy and if they're not tight enough, the buttons might not function or even stay in their down position. Soldering the terminals and button's back in their place is generally all that's required to return a non-working key fob to working condition.
Non-Remote Transponder Chips
Sealed non-remote transponder chips are more durable than the remote fobs that have them but they can still be broken by a hole being that is drilled into them or over by a lawnmowers or door handle for a car. Most of the time, non-remote transponder chip failures could be attributed to an exploded fuse.
If you're handy enough to remove a key fob that is sealed and are willing to put up with the mess, you can take off the circuit board and examine the fuse with an instrument to verify diode function. If you're not sure with this, visit your local Oreilly or hardware store and utilize their RF frequency tester. This will let you know whether the key fob transmits a signal.
Programming
Key fobs aren't indestructible and can be damaged by a variety of factors. They may lose their connection with the receiver in your vehicle due to shocks or a low-battery, which requires changing the program. A professional auto locksmith or a main dealer can reprogram your key fob to get it functioning again. In the rarer case that resetting and fixing your key fob fails it may be time to replace it entirely.