[300bps]

The issue of taxi drivers lying and saying their machine is broken when it isn't is so rampant they even cover it in the FAQ you linked to!

>What if a driver says the system is not working? The passenger should note the medallion number and go to 311 Online. Drivers are permitted to work with a broken system for up to 48 hours as long as they have reported the problem and are awaiting repair. Almost all (90%) system repairs must be completed within six hours.

And there isn't much you can do about it except threaten to complain and hope the taxi driver relents and lets you use it.

[yolesaber]

You can also just get out of the cab. I usually throw em any cash if I have it on me but not my fault you just drove me to the airport and forgot to mention your card machine doesn't work.

[cballard]

If you call 311, TLC will slap a $300 fine on them, so taking out your phone and doing that will instantly fix the machine.