How to Fix a Key Fob That isn't Working
If your key fob won't work and you're not sure why, you can fix it by following just a few steps. 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 circuitry or battery issues.
Battery
It is not unusual for the battery inside the car key fob to get worn out. It is fairly easy to change out batteries, but it is important to ensure that you use the right type that you can refer to your owner's manual or contact the dealer of the manufacturer to find out what kind of battery you require. It is also crucial to inspect the battery compartment as batteries that are not working properly can release 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 professional attention. For instance, if the buttons seem to be 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.
Buttons
Key fobs can become filthy and worn out due to frequent use. It is not uncommon to have buttons stop functioning, or require a hard push to make them work. This can be a hassle, especially when you are away from your home and have to turn on your car. Even broken or damaged buttons can be fixed with a little effort and tools you already have at home.
First, make sure that the batteries are correctly placed and that the indentation at the back of the button has been filled. Then, carefully open the remote and look at the circuit board. Check for signs of corrosion or other indications that the buttons are worn out or damaged, like missing conductive paint. Use a Q-tip dipped into rubbing alcohol to gently clean any membrane contact that is damaged or has conductive paint missing. Do not rub too vigorously as this can damage the conductive paint and prevent the button from firing when pressed.
Check the battery connector terminals carefully for any loose solder connections. If this is the case, simply reconnecting them may bring back function to the button. You can use the same method to restore functionality to any other loose connection inside the fob.
In the end, if 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 that the graphite disks on the back of the button are wearing down and require replacement. You can do this by rubbing a pen across the disks. This should bring the button to life.
If none of these solutions work, or if you still cannot get the button to respond when pressed hard, it is possible that the circuitry is failing. It is possible to fix this by cleaning and re-soldering your fob, but you should have a spare in case it doesn't work.
Circuitry
Whether or not the key fob buttons function the circuit board in your remote might be dirty. This issue can be fixed through a thorough examination. Water and broken cases are the most common causes of dirty boards. A broken case allows water and other debris to get in and short out the electronic components. car key circuit board repair can also damage pins and vias, which are tiny connectors found on the board.
If you're able to open your key fob, and you don't mind making a mess, we can take the buttons out of their sockets and put in new ones. Also, it's worth checking the connections between battery terminals. If they are loose, the buttons might not function properly or become stuck in their down position. Soldering terminals and buttons back into place is usually enough to return a malfunctioning fob to a working condition.
Non-Remote transponder chips
The non-remote chips that are sealed are more durable than remote fobs, however they can be cracked in the event of a hole being drilled in them or if a car door handle or lawnmower runs over them. Failures of the fuse are typically to blame for non-remote chip failures.
If you are not comfortable opening the key fob, remove the circuitboard and use a multimeter to determine if the diode is working properly. If you're not comfortable doing this, visit your local hardware store or Oreilly's, and they will usually have an radio frequency tester that can determine whether the key fob sending signals.
Programming
Key fobs aren't impervious to destruction and are susceptible to being damaged by a variety of factors. They can lose their pairing to the receiver in your car due to shock or low battery, which calls for them to be reprogrammed. A professional auto locksmith, or a dealer in the main can reprogram the keyfob to get it functioning again. If resetting or fixing your keyfob does not work it is possible to replace it.