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Symptoms of a Bad or Failing Key Fob Battery

key fob battery

In the world we live in today, the use of fob security authentication is used in multiple areas. From the hotel keys that we use to enter our room, to the keys that unlock the doors and trigger the ignition system for our vehicles, we depend on fob to provide secure access to networks we utilize daily. Many of the cars, trucks and SUV's use key fobs as a more secure and convenient replacement to older manual key systems. However, in order for these fobs to work, they need to have a fully functioning battery, which as with any battery will eventually wear out.

Most of the key fobs that are on the market today are very complicated pieces of equipment and can cost the vehicle owner a considerable amount of money to replace. One of the major causes of replacement is that the battery wears out and is not replaced in a relative quick time. If the battery completely dies, the fob chip will also lose power and become useless unless reprogrammed directly by the automotive manufacturer.

In order to avoid this potential problem, it's important to know the warning signs of a bad or failing key fob battery. Listed below are a few of these symptoms that will alert you that it's probably time to replace your fob battery.

1. Reduced signal strength

Most of today's fob keys will send a signal to the vehicle up to 50 feet in many cases. Many car, truck and SUV owners utilize this function as they walk away or are approaching their vehicle and want to unlock or lock their vehicle. As the battery wears out however, the range and signal strength of the fob transmitter will be reduced. If you notice that your key remote does not unlock your car, lock your car, or start the engine for those with the automatic start button as early as it should, it's probably time to replace the battery.

2. Multiple clicks needed to unlock the doors

For the most part, a fully functional key fob will be able to unlock the doors on a car in just a single click. When it starts to take more effort to unlock the doors of the car, this is commonly a sign that the battery has worn out and needs to be replaced. Most fob batteries for keyless remotes are sold at hardware stores even big box retailers like Target, Walmart and others. It's best to replace the battery in all remotes at the same time, as they are often sold in pairs.

3. The key fob does not work consistently

When the key fob is working correctly, it activates anytime a button is pressed. However, some of the newer keys are also responsible for triggering the ignition system. In this case, they are either inserted into a slot on the dashboard, or they send an electronic signal to the vehicle ECU to permit the driver to press a "start" button. When this function becomes inconsistent, it's is usually due to the battery inside these keys wearing out. Finding a quality replacement battery for the key fob is the best way to get it working efficiently again. Be sure to remove the old battery from the key fob to get an idea of what type is required for your specific key. It's also common for automotive manufacturers to put this information in the owner's manual.

One thing you want to avoid if possible is making sure not to let your key fob battery wear out completely. This can cause the fob sensors to reset, meaning that they won't connect to your specific vehicle. If you have any problems finding the right information or don’t feel comfortable replacing the fob battery, contact a local ASE certified mechanic who will be happy to assist you in this effort.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
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