Clipper autoload is broken

Fred C. ‏@oddnoc
Dammit. Just remembered my Clipper card is empty. And don’t tell me to use autoload. That system is shamefully broken.

Jay‏@hackerjay@oddnoc
How is the autoload system broken? I’ve been using it for a couple of years and haven’t seen any problems. Is it a security issue?

Through my employer, I can fund my transit expenses with pre-tax funds. This is done through WageWorks, which does a great job. The money goes into an account that’s accessed via a specialized MasterCard.

I had linked the MasterCard number to my Clipper card for autoload (actually, it’s one of the old, Translink-branded ones). Whenever the value of the card falls below $10, autoload is supposed to add a user-definable increment to the card. Here’s how it works:

  1. Have $11 on the card
  2. Ride Muni, reducing the card value to $9
  3. Autoload kicks in, incrementing the value of the card to, say $29
  4. Clipper attempts to charge the linked account, which at the moment, has, say, $19.95 in it
  5. Oh no! Insufficent funds!
  6. Clipper card, including the legitimate $9, is blocked
  7. No more transit for you!

Why don’t they swap steps 3 & 4?

The last time this happened, the Clipper customer service representative admitted how broken this is, and advised never using autoload with a commuter debit card, and so I don’t.

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One thought on “Clipper autoload is broken

  1. They can’t swap steps 3 & 4 because Clipper is a store-and-forward system and none of this happens synchronously.

    At the time that the reader “meets” your card, and sees that you have autoload set up (this info is stored on your card) and are below your target balance, it simply has to trust that you’ll be good for the $20 that it adds.

    When the night’s transactions are run and the MTC actually attempts to debit your account and fails, they submit a job that blocks your card. This blocking occurs the first time your card “meets” a reader the next day.

    To do it any other way would either require your autoload to process a full day later, potentially denying you the ability to ride, or could set up MTC to be easily defrauded.

    The solution is to make sure there’s enough money in your bank account.

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