How To Fix an AP C Series vending machine keypad freeze and does not function when pressing any button

I recently have an AP C Series snack vending machine moved to a recycling factory in Surrey which was extremely busy even with the Pandemic crises.

I have not been to the location for a month and was just there yesterday and very excited to service it since I’m sure that it will be quite empty.

To my surprise, the AP C Series Vending machine keypad display just shows the number 8 and still full of products.

It just freezes and no matter what button i press it simply just shows 8.

This comes to mind that there are several factors to be considered.

Here are some of the problems which might be causing the Keypad Freeze:

Not enough power to the mainboard
Mainboard component nearing the end of life
Defective Keypad
Defective Coin Mechanism

According to my experience, I used to have an AP SnackShop American Products Snack Machine Model 113 which is non MDB and when i changed the coin mech everything works great.

I also used to have another AP SnackShop american products model 112 showing erratic prices when the keypad is pressed, I found out that some components inside the power supply is nearing its life.

This location was giving me problems ever since, I have already changed 3 snack machines on this location.? The 1st snack machine was there was no mainboard available so I have to throw it away, since the mainboard here in Canada costs around $550.? With $550 I can buy a used snack machine at Craigslist.

The 2nd machine I remembered was the door was partially vandalized on the side.? I had the have it moved to my garage and repaired it for another location.

The 3rd machine is the recent AP C Series Snack machine were it was perfectly working fine and after a month the dispplay just freezes with the number 8.

This was my first time I encountered a keypad number freezes.

So How did i fix the AP C Series Snack machine keypad freeze?

Remember I got vandalized before with 3 AP C Series vending machines and luckily I did not toss the spare C Series machines which I was able to salvage for some parts.

If I called a vending machine repair technician it would have cost me:

1.? Call out fee just to the inspect $125!

2.? The technician will go back and buy keypad parts which will cost around $60 ( Technicians normally multiply the cost of the parts by 3 to 4X times, the real price of the keypad if you buy it online is around $15 to $35 at the most )

3.? Technician go back to the location and install parts, will cost another whopping $85!

You would have lost $125+$60+85=$270!

How many chips and chocolate bars are needed just to cover the $270?!?

I suggest for all electrical servicing, you have to do everything by yourself.