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 just a few steps. The first step is to be sure it's not the backup remote.
If your backup remote is unable to unlock and lock the doors of your car, then it is most likely that the primary remote isn't working. The most common causes of key problems with your car remote are issues with the circuitry or battery.
Battery
The battery inside a key fob can wear out over time. It is fairly easy to change out batteries, but it is important to make sure that you select the correct one that you can refer to the owner's manual or talk to the dealer of the manufacturer to find out what kind of battery you require. It is also crucial to inspect the battery compartment, as dead batteries can leak caustic chemicals that can harm the remote. If replacing the batteries doesn't solve the issue it could be because there are other issues that require attention from a professional. For instance, if the buttons seem to be stuck or broken It may be necessary to disassemble the remote and rework its parts. You can also try reprogramming the vehicle to recognize the new fob.
Buttons
Key fobs may become filthy and worn out due to repeated use. This is not uncommon however, it can cause buttons to stop functioning or require a long press to work. This can be frustrating, especially when you are away from home and have to turn 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 home.
First, ensure that the batteries are up correctly and that the indentation on the back of the button is filled. Then, carefully open the remote and examine the circuit board. Examine for indications of rust or other signs the buttons are damaged or worn. For example the paint that conducts electricity could be missing. Use a Q-tip dipped into alcohol to gently clean any membrane contact that has become worn-out or has conductive paint missing. Avoid rubbing too hard, because this could damage the conductive painting and prevent the button from firing when it is pressed.
Check the battery connector terminals carefully for any loose solder connections. Soldering them back to their original position will restore the button's functionality If this is the situation. The same method can be used to restore functionality to any other 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 at the back of the button may have worn out and require replacement. It is usually done by rubbing a pen over the disks. This will bring the button back to life.
If all of this doesn't help, or if the button still does not respond to a firm press It could be that the circuit board has gone bad. It is possible to fix this issue by cleaning and re-soldering the button however, you should have a spare in case it does not work.
Circuitry
Whether or not the key fob buttons function, the circuit board inside your remote may be dirty. car key fob repairs can be resolved by a thorough inspection. The most common causes of dirty circuit boards is water and broken cases. A broken case allows water and other debris to pass through and short out the electronic components. Water can also destroy pins and small connectors on the board called via's.
If you are handy enough to open your key fob and you don't mind making a mess, we can remove the buttons from their sockets and solder in new ones. It's also worth examining the battery terminal connections. They can become 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 putting the button back in place is usually all it takes to restore the key fob that is not working to functioning condition.
Non-Remote Transponder Chips
Sealed non-remote transponder chips are much more durable than remote fobs that contain them but they can still be broken by a hole being drilled into them or run over by a lawnmower or door handle for a car. The majority of non-remote transponder chip malfunctions can be blamed on an exploded fuse.
If you're not comfortable opening the key fob, you can remove the circuitboard and use a multimeter to determine if the diode is functioning correctly. If you don't feel comfortable with this, visit your local Oreilly or hardware store and utilize their RF frequency tester. This 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 break their connection with the receiver in your vehicle because of shocks or a low battery, which calls for the reprogramming. A professional auto locksmith or main dealer will be able to reprogram your key fob and get it functioning again. If, in the unlikely event that resetting and repairing your key fob doesn't work it could be the time to replace it entirely.