I'm trying to repair a soda machine for the nursing facility I work for. It has day outside unused for a few years, but has been left plugged in. The refrigeration side of things works great. The display works, it cycles through the menu items fine - but when trying to use in normal mode - the display just displays all 0's. Also when going into the price setting - it just displays 00000 and will not let me change it. The coins just drop through and the bill acceptor won't take bills, but I'm guessing that has to do with the price issue.
I'm pretty familiar with electronics and have worked on some vending machines but this one has me stumped. Any help would be greatly appreciated.
or a bad logic board. Since it cycles through the menus and you have gotten to the pricing menu that tells us your door switch is working and putting you in the service mode when you open the door. In the pricing menu, you should be able to press any selection button and hold it as that selection's price rises. You can release and press again and the price for that selection will decrease. Wherever you leave the price, it will be saved to that selection. You will then move to the next selection button. What's odd is that even if your board lost it's price memory, it would default to $99.95, not zeros. If none of this happens while S-P is on the display, then you have a bad logic board. This would also explain the reason your coins drop through the coin mech. One thing you should do before replacing the board is to power the machine off, disconnect the bill validator and coin mech then power up again and try to price it. If the pricing now works properly then either your coin mech, bill validator, or both are bad.
If you need any parts for this repair you can send me a message by clicking on the Send Email button below my screen name.
I checked it with the coin and bill changer unhooked and that didn't change the behavior at all. Another weird symptom (not sure if related) is that the bill acceptor doesn't have the red light lit that designates power and normal operation. But if I press the button on it, the light will flash.
How certain is it that the main control is bad with the 0000 symptoms. What's a replacement cost?
The red LED on the validator (what you describe is a Mars VN2500) is only on solid when the machine is enabling bill acceptance, which it isn't doing right now. To enable bill acceptance with a properly operating machine you will need product in one column and coins in your coin mech tubes. Pressing the button on the rear of the validator only puts the validator into coupon mode and means nothing.
I don't post prices on any public forums so as not to start any price wars (but you'll be under $200), so please send me an email and I can help you out.