What are the most common reasons for a bill validator to repetidely reject bills?

[Randy 805]

What are the most common reasons for a bill validator to repetidely reject bills? I have a Vendo unti with a Coinco Model MAG50B bill validator that although the validator is empty it keeps on rejecting most bills I try to feed into it... There are sufficient variances of change available in the coin mech. to dispense change for both a $1 or $5 bill, but the validator keeps taking the bill, then spitting it back out, I've cleaned the lenses on the sensors, and the belt / wheels do look a little worn, but I ould think that would only affect taking the bill into the validator, I don't understand why it keeps spitting them back out...

[Vendors Tech]

The validator probably needs calibrated. A good servicing wouldn't hurt it either. One thing you can try is to pop out the main micro chip on the control board of the unit, then pop it back in again. (if its soldered directly to the board, you won't be able to do this.) If its a removable chip, it will be sitting in a brown socket on the upper part of the board. The chip CAN ONLY GO BACK IN ONE WAY. You need to line up the dot on the bottom of the chip with the arrow on the socket when you replace it.

Its probably going to need calibrated though. Coinco does it for just $15, but make sure you are adamant that THEY JUST CALIBRATE IT. I have sent them units before, and they rebuild the whole unit in defiance of the notes I include telling to JUST CALIBRATE IT! And their rebuilding prices are ridiculous, usually WELL over $100-$120. I would actually recommend finding an independent company who has the calibrating capability, and have them do it, they usually care about the customer. Companies I know that have the software are:

Vendors Exchange, Eastern Commercial Services, Technivend, Vending Works. Look them up online. Hope that helps.

Most charges for calibrating are $10-$15 from all those places.

[Randy 805]

Great response, thanx!