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 with just a few steps. First, check to make sure it's not the backup remote.
If your backup remote can unlock and lock the doors of your car, it is most likely that the primary remote isn't functioning. The majority of car remote key malfunctions result from circuitry or battery problems.
Battery
It is not unusual for the battery inside the key fob for cars to wear out. It is fairly easy to replace a battery, although it is important to ensure you select the correct one that you can refer to your owner's manual, or contact the manufacturer's dealer to find out what kind of battery you need. It is also important to inspect the battery compartment as batteries that are not working properly can release toxic chemicals that could damage the remote. If changing the battery doesn't fix the problem there may be additional issues that require attention from a professional. For instance, if the buttons seem to be stuck or damaged It may be necessary to take the remote apart and rework its parts. You could also try reprogramming the vehicle to recognize the new fob.
Buttons
Key fobs may become dirty and worn-out from repeated use. This is not uncommon, but it can cause buttons to cease working or require a very hard press for them to function. This can be very frustrating, especially when you are away from home and have to turn on your car. Even malfunctioning or worn-out buttons are often fixable with a little effort and materials you already have at home.
First, make sure that the batteries are correctly installed and that the indentation at the back of the button has been filled. Take the remote apart and examine the circuit board. Look for signs of corrosion or other signs that the buttons are worn or damaged, like missing the conductive paint. Use a Q-tip, dipped in rubbing alcohol to gently clean any membrane contact that is worn out or where conductive painting is missing. Avoid rubbing too hard because this could damage the conductive painting and prevent the button from firing when it is the button is pressed.
Check the battery connector's terminals for loose solder connections. Soldering them back into place will allow the button to function again if this is the case. The same procedure can be used to restore function to any other loose connections in the fob.
If any of the rubber buttons on the front of the keyfob isn't functioning or require to be pressed very hard the graphite disks on the back of the button might have worn out and require replacement. You can usually do this by rubbing a pencil over the disks. This should 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 has failed. It is possible to fix this by a quick clean, and re-soldering, but it is ideal to have a spare fob on hand in the event that this method does not work for you.
Circuitry
The circuit board of your 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 frequent causes of dirty circuit boards is water and damaged cases. A broken case can allow water and other debris to enter the circuit board, which can cause it to short. Water can also destroy pins and small connectors on the board, referred to as via's.
If you're able to remove your key fob and aren't afraid of making a mess, we can take off the buttons and put new ones in their place. It's also worth looking at the battery terminal connections. They can get very dirty and if they're loose the buttons might not function or even stick in their down position. Soldering the terminals and button's back into place is typically all that's required to return a non-working key fob to working order.
Non-Remote transponder chips
Sealed non-remote transponder chips are more durable than the remote fobs that contain them but they can be broken by a hole being made in them or pushed over by a lawnmowers or car door handle. key repair of the fuse are typically to blame for non-remote chip failures.
If you're not comfortable opening the key fob, you can remove the circuitboard and utilize a multimeter to verify that the diode is operating correctly. If you're not sure with this, you can go to your local Oreilly or hardware store and utilize their RF frequency tester. This will inform you whether the key fob sends signals.
Programming
Key fobs take lots of abuse and aren't indestructible. They can break their connection with the receiver in your vehicle because of shocks or a low battery, requiring changing the program. A professional auto locksmith, or a dealer in the main, can reprogram your key fob and get it back functioning again. If, in the unlikely event that resetting or repairing your key fob fails, it could be time to replace it entirely.