How to Fix a Key Fob That isn't Working
If your key fob isn't functioning A few easy steps can be taken to fix it. First, check to make sure it's not your backup remote.
If the backup remote is able to lock and unlock your car door, then there is likely an issue with the main remote. The most common causes for key malfunctions for car remotes are issues with the circuitry or battery.
Battery
It is not unusual for the battery in the car key fob to degrade. It is simple to replace a battery. However it is essential that you choose the right type. You can check your owner's guide or contact the manufacturer to determine the right type. It is also essential to inspect the battery compartment, since dead batteries can leak caustic chemicals which can damage the remote. If changing the batteries does not solve the issue it could be that there are other issues that require attention by a professional. For instance, if the buttons appear stuck or broken It may be necessary to disassemble the remote and rebuild its components. You could also try reprogramming your car to recognize the new key fob.
car keys repair can get dirty and worn-out from repeated use. This is not atypical, but it can cause buttons to stop functioning or require a long press to function. This can be very frustrating especially if you're away from home and you need to start your vehicle. Fortunately, even worn out or damaged buttons can be fixed with a bit of time and a few materials you might already have in the house.
First, verify that the batteries are correctly installed and that the indentation at the back of the button is filled. Then, carefully open the remote and look at the circuit board. Examine for signs of rust or other signs the buttons have been worn or damaged. For instance there could be conductive paint missing. Utilizing a Q-tip dipped in alcohol to gently clean any membrane contacts that have damaged or have conductive paint missing. Do not rub too vigorously as this can damage the conductive paint, and block the button from firing when it is pressed.
Examine 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 functionality to any other loose connections within the fob.
Finally, if any of the rubber buttons on the front of the key fob stop working or require a hard press to work it is likely the graphite disks that are on the back of the button are wearing out and require replacement. This is usually done by rubbing a pencil across the disks, which will bring the button back to its original state.
If all of this doesn't help or if the button does not respond to a hard push, then it may be the case that the circuit board has become damaged. 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 fails for you.
Circuitry
The circuit board inside your remote control may be dirty regardless of whether the buttons on the key fob work or not. This issue can be fixed through a thorough examination. The most common causes of dirty circuit boards is water and damaged cases. A broken case can allow water and other debris into the circuit board, causing it to short out. Water can also damage pins and connectors on the board called via's.
If you're skilled enough to open your key fob, and aren't afraid of making an mess, you can remove the buttons from their sockets and solder in new ones. It's also worth checking the battery terminal connections. If they're loose, the buttons may not work or even become stuck in their down position. Soldering the terminals back to their proper positions is usually enough to bring a non-working fob to working.
Non-Remote transponder chips
Sealed non-remote transponder chips are more durable than the remote fobs that have them but they can be broken by a hole being drilled into them or run over by a lawnmowers or car door handle. Most of the time, non-remote transponder chip malfunctions can be blamed on an exploded fuse.
If you're not confident opening the key fob, take the circuit board off and use a multimeter to determine if the diode is working correctly. If you're not comfortable doing this, head to your local hardware store or the Oreilly's and they usually have an RF frequency tester that will tell you whether the key fob is sending signals.
Programming
Key fobs take a lot of abuse and aren't indestructible. They may lose their connection with the receiver inside your vehicle because of shocks or a low-battery, which requires reprogramming. A professional auto locksmith or dealer can reprogram your key fob and get it working again. If, in the unlikely event that resetting or repairing your key fob fails, it could be time to replace it entirely.