Why Key Cards Stop Working and How To Make Them Work Again 

Whether you have a key card you use regularly for work or you were issued one to get into a hotel room, more than likely, you’ve had the experience of trying to use an inoperable key card. While convenient and typically easy to issue, key cards are known to become demagnetized and stop working. 

Here, you’ll learn why key cards stop working (so maybe you can avoid the problem altogether in the future) as well as how to make a key card work again. 

why bypass key card lock

What Is a Key Card?

A key card is a plastic card used for access control. Typically, they have a magnetic stripe that holds information about the user. Key cards can also be equipped with radio frequency identification (RFID) technology

Often used in hotels and on school campuses, these cards can be used for any secure location that requires users to have some sort of key to gain entry. They’re convenient for hotels, resort properties, and college campuses because they can also function as a credit card throughout the property. 

Key cards are programmed to work in certain locks; when you check into a hotel or are issued a card, you are granted access to your hotel room or other specific areas. Key cards can easily be reprogrammed for new guests.  

You can tell the difference between a magnetic stripe card and an RFID card in two main ways: a magnetic stripe card will have a black stripe on the back while an RFID card will not. Additionally, you need to swipe or insert a magnetic stripe card into a card reader while an RFID card only needs to come in close proximity to a card reader. 

Types of Keycards

Why Do Key Cards Stop Working? 

When you run into a key card that isn’t working anymore, you’re most likely using a magnetic stripe key card. 

Here are some reasons magnetic stripe key cards can stop working:

  • The card becomes demagnetized. This can happen if the card gets too close to a strong magnet, such as an MRI machine. It can also happen if the card spends a moderate or long amount of time next to a weaker magnetic object, such as a cell phone or set of keys. When the card gets demagnetized, the data gets erased from the card. 
  • The card gets physically damaged. A key card can become physically damaged for several reasons; it can get crunched, ripped, or scratched. The card can also become damaged if it gets wet. Damage can even happen simply due to wear and tear over time. 
  • The battery is dead on the lock. This isn’t a problem with the card itself, but a dead battery in the lock will cause the key to stop working. 
  • The card gets exposed to extreme heat. Extreme heat can erase data and make the card not work. 
  • The card is dirty. If there is too much buildup of dirt and debris on the magnetic stripe, the card reader won’t be able to read it correctly. 
  • User error. Many card readers function differently from one another, making it difficult to always use a reader correctly, especially if you are used to a specific type of reader. Sometimes users insert the card in the wrong direction or they insert it too quickly or too slowly. 


RFID key cards can stop working as well, but they don’t often have the same issues as magnetic stripe cards because RFID cards don’t rely on magnets and thus can’t be demagnetized. Some issues can plague magnetic stripe and RFID cards alike, such as a dead reader lock or a damaged card. 

Another main reason an RFID card can stop working is if you have multiple cards close together as you might in a wallet. If you have many cards in your wallet (think credit cards, ID cards, store loyalty cards, etc.) and you try to scan your RFID card through your wallet, the cards could interfere with each other. 

How To Make a Key Card Work Again 

To make a key card work again, first try troubleshooting through some of the easier fixes. You can try to clean it off with an alcohol wipe and check for obvious damage. You can also try gently cleaning the magnetic stripe with something rough; just don’t scrub too much or you risk damaging the card. If there are scratches or damage on the stripe, you can also try putting tape over the magnetic stripe. 

Make sure you’re following the directions of the reader as well. Take time to insert the card facing the correct way and try swiping it at different speeds. If you need to insert the card, try leaving it in longer or taking it out faster. Additionally, ensure that the battery isn’t dead on the card reader. 

For RFID cards, try holding the card closer to the reader and keeping it there for a longer or shorter period of time. You should also try removing the card from your wallet or separating it from other cards when you’re trying to scan it in case they’re causing interference. 

Of course, if the data is erased from the card or the card is damaged beyond repair, you’ll need to either have the card reprogrammed or entirely replaced. If you’re at a hotel, this can be done at the front desk. Otherwise, you’ll need to contact the issuer or manufacturer of your card to have it replaced or reprogrammed. 

Lastly and importantly, make sure you cut up or destroy your old card if you need to have your key card replaced. 

key card lock

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