If a card is not working at a door reader, you can troubleshoot the cause of this issue.
Make sure you are using the right type of card technology for the reader.
For example, some readers are multi-technology (can read 125 kHz and 13.56 MHz cards), and other readers can only read one card type.
- Test if the card is defective by trying another card.
Test if the reader is installed too close to another reader by disconnecting the power
to one reader.
If the other reader starts to operate correctly, they were installed too closely. Readers emit an electromagnetic field that can interfere with other readers located nearby.
Test if your are using the proper cable for the reader by connecting a spare reader
directly to the unit with a short cable.
If the spare reader works, you should change the cable of the original reader. For the maximum cable length and type, see the reader and unit documentation.