A light-hearted post: Ever have a stay of >2 nights and your keycard no longer works?
Mystery solved: upon checking in, the front desk runs the keycard through an "imprinter" which magnetizes the magstrip with room number and nights. The default setting is for 2 days and for >2 days, the clerk MUST put in the number of nights. Sometimes the clerk misses this and your card stops working. (The machine is not wired to reservations computer, so manual operation is required.)
Of course we've been told that cell phones can degauss the card. Based on my informal tests, I have never been successful at degaussing my card using direct cell phone contact (Samsung, LG, and Blackberry models in the last year). Because I almost always end up getting 2 cards at check-in and consequently, leave one in my room, I've been able to observe that when the one I carry fails, the one left in my room has failed, too (seems to always happen on day 3).
My observations and cell phone tests suggest it was not keyed up correctly for number of days at check-in.
Dear Pingreeman, yes that's happened to me, and there appear to be a number of culprits. Putting the card in wallet with credit cards seems to have some effect and occasionally it will demagnetize the key card.
The villain in this whole key card demagging kerfuffle is the proximity of magnets to the card. My cheap cell phone sits in a small purse on my ample waist, and of course the lid of that purse is magnetized to keep me from losing my phone to gravity. Even passing that little magnet seems to make my key card incapable of working. At one 5 night stay I had five different key cards. I am a slow learner, but as the associate kindly said, "perhaps it's your magnetic personality?"
I talked with a friend at Marriott and confirmed you are correct. As you said, cell phones, credit cards, etc., can affect the key card but when that's one of two cards and the second one is on the coffee table in your room, that doesn't explain why it, too, does not function. So again, thanks for the post and I will remember to confirm the nights my key cards are programmed for from now on.
It happened at Marriott's Custom House to both sets of cardkeys. Custom House is a tower with 26 floors. Using the key card, registered guests can get to the common floors, 23-26 and to the floor where their suite is. We came back from dinner and the card key did not work. Number of nights was the culprit.