Reasons Your Fiat 500 Key Fob Won't Work A key fob from Fiat 500 makes it simple to open doors and start your car. There are a myriad of reasons the fob could stop functioning. This could be due to a dead battery and water damage, as well as problems with the receiver modules, and interference. This listing is for a NEW replacement Fiat Flip Key Remote - like the Ilco brand that must be programmed professionally by a local locksmith (click here for Locksmith Search). This remote includes lock, unlock and trunk buttons. Dead Coin Battery The most frequent reason why your 500 key fob doesn't function is a dead battery. Modern key fobs come with a limited operating range and must be within a few feet of the vehicle to function. If you are not within your vehicle and hit the keyfob, it will not respond, and display the message "Key Fob Not Detected". If this happens, replace the battery in the coin cell (Part number CR2032) with a new one from a reliable brand like Panasonic, Duracell, or Energizer. You can typically find them in your local hardware store, or online. After you've replaced the coin cell battery It is possible to test it by standing near your Fiat 500 and pressing the buttons. The car should blink its parking lights, and the key fob should operate the lock and unlock switches. If your key fob doesn't work even after replacing the battery, it might be water damage that prevents it from interacting with the module inside your vehicle. https://www.thekeylab.co.uk/fiat-car-keys/ can happen in a number of ways, ranging from small splashes to submerging the fob in salt water at the beach. If you believe your fob was exposed to water, you can place it in a rice bag to draw out the moisture. If this doesn't work the fob might need to be reprogrammed by a professional locksmith or dealer. Water Damage Damage to the water supply can occur if you immerse the fob into the ocean, or wash it in a washing machine. Saltwater can be particularly harmful to the fob's circuit board that can cause it to short out and eventually die. It's not the best idea to get the fob wet however, but don't give it up if you accidentally drop it in water, or fail to remove it from your pocket. First remove the battery from the fob. Clean the electronic chip using isopropyl or a similar product and dry it thoroughly before replacing the battery. Then test the fob to verify if it is working. If the fob doesn't work it could need to be programmed again. This is typically handled by a dealer or professional auto locksmith. If the key is older and was not programmed to your car It is likely that it needs to be replaced completely. This is a simple process which can be accomplished by a professional locksmith for automotive use. The locksmith will need the key to be cut to match your vehicle's ignition. The locksmith will also need to reprogram the fob into the car's system. This is a simple and affordable process that can be completed the next day. Receiver Module Issues One of the most common reasons your 500 key fob may stop working is that it's simply out of range. The remote has a range of 30 feet. Therefore, in the event that you are far from your vehicle it won't respond to your commands. This can be easily fixed by moving closer to your vehicle until it begins responding. If you've replaced the coin battery (commonly known as a "button" or "watch") and the fob isn't working, it could have an internal circuit board problem. Reprogramming the fob typically resolves this issue. The instructions are available for most vehicles on YouTube or in the owner's manual. It's possible that you need to replace the metal clips that hold the battery of your coin in place. If they become loose, it could prevent your coin battery from being properly seated and cause your remote to malfunction. In rare instances, the fob might be out of sync with your vehicle because of software or hardware problems. This could cause a significant issue, but you are able to usually fix it by visiting an auto locksmith to have them reprogram your fob. In some instances the software might need to be reinstalled in your body control modules. Interference Interference can also cause the key fob to not receive or transmit a signal. This can happen when the key fob is located near a radio transmitter (cell phones and radar detectors) or any other source of electromagnetic radiation. Other reasons why the key fob might not function may be a lack of connection to the buttons or damage to the internal chip, or water damage. If the key fob stopped working one day without notice, or after trying everything you can at home to solve it e.g. replacing the battery, reprogramming it and using the spare key fob, it could have a malfunctioning receiver module on your 500. The receiver module is located under the dash and receives the radio frequency signals from the key fob. It converts them into electronic commands that the vehicle interprets. Fortunately, there's an easy method of resetting all on-board systems in your 500 device, including the key fob. Disconnect the battery for 15 minutes by taking off first the negative cable and then the positive cable. Then, reconnect the battery. This will eliminate any remaining electrical charge, and then restart the computer of your car. This can help you get your key fob to work again. If the issue continues it is recommended that you consult a certified technician. They can diagnose the exact cause of your problem.