Resetting the RAM on Universal Slot (Error 21)

[MODELAWIZARD]

Hello!
How can I reset the RAM on my Universal Slot? 1994 model
Error Code 21
What are the next steps?
Any other resources out there?
Thank you!

[UNIMAN]

Somehow missed this post!


Pressing the yellow reset switch at top righthand corner of door frame resets error 21.
Error 21 is coin-in jam. There are two grey optics in the coin track located in the door. If one of these optics is malfunctioning you will get the error. The machine measures the amount of time a coin takes to pass the upper optic and then the lower optic as it free falls through the coin track. This is there to detect the "coin on a string" trick used by cheats.
Malfunctioning can be caused by something blinding one or both optics such as a piece of paper, fuzz, etc. The optics have one screw holding them in place. Remove the optic and wipe with a dry Q-tip. Reinstall and test it.
You can test the machine with the door open by pulling out on the white door switch and then blinding the door lock optic by locking the door while open or put a piece of tape over the door optic. Once the machine thinks the door is closed and locked the INSERT COIN light will flash. Insert a coin while watching the two coin optics. There is a small red LED that flash on each optic as a coin passes. The LED should normally be off and only light up as a coin passes. Most machines have a third optic where coins are diverted when a hopper is full. This third optic sits lower than the two coin-in optics, You can use this third optic as a spare. It is not needed for home use.


Hope that helps, sorry for delay!