The old "cover Open" error is common on the ER-5200 Samsung registers. The error is not about the big cover above the printers but the covers that you raise and lower when putting paper in the printers. The little switch on the right side of the cover when closed has become defective. There is a permanent cure for this but you will have to take each printer out of the machine. Remove the paper, remove the little white cover on the front of the printer by removing the screw on the left of that cover. In the bottom of the printer you will see 2 screws, remove them. On the front of the printer there is also 2 screws, remove them. There is a ground wire on the right side of the print held down by a screw. Remove that screw to free up the ground wire. Lift the printer up. If you can see the bottom of the printer and the right side of the printer that will be great. look at the right side of the printer and you will find a tiny micro switch. Follow the 2 wires to the little printed circuit board on the bottom of the printer to where they are connected. Now what we have to do is cut those 2 wires and skin back the wires near where they are plugged in and twist the 2 wires together and then insulate the with electrical tape. Do nothing with the wires running to the switch, just let them hang there. Shorting the wires tells the machine the cover is closed all the time. Now it is almost impossible to tell which printer, since there are 2 printers (receipt and journal)in the ER-5200, which one went bad. So you have to do the same thing to the other printer. If you don't do both now chances are the other will go bad in some months down the road. So do some preventive maintenance and do both printers.
Robert
May 2015
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