Prefill your machine’s coins through the coin slot:
- Arrow down to “Cash Prefill” and fill the machine with coins.
 - Add coins until your coin tubes are 2/3 full. The machine should be registering each coin you insert.
 - When done, hit the “enter” key.
 - If the lights aren’t lit on the bill validator, the motherboard doesn’t think you have enough change in the coin tubes.
 
