The error message was something like "out of order switch error". I thought I solved the problem because someone left this "Simoniz tire shine gel". The Simoniz pad was not the problem. So I had to move the vending machine. (A real pain.)
After I moved the machine it did not have power. (The vending machine is on a lazy Susan and you have to turn it 180 degrees.) So I assumed the cord was unplugged, but I somehow blew the breaker. I checked out the machine and everything looked normal. So I reset the machine, pressing in the yellow button. After that magic.