Solution to red light after refill Samsung ML 1540

Samsung printers such as ML 1640,ML 2245 and SCX 4300 have a toner page count embedded in their firmware. This is the reason that once you refill your toner after it has run out,the printer still doesnt print and says toner is exhausted. After you've refilled the cartridge,you'll have to reset the toner count also to zero...to do this,download the firmware here. ML 1640 Ml 2245 and SCX 4300 are not available on Samsung support site. You will need to google it and you may find it in torrents.

run it and it will reset your toner count to 0...you have to do this everytime you refill your toner.
Another solution is to open the backside of ML 1640 and ML 2245,locate the chip 93c66 and short pin numbers 1 and 4 and turn on the printer for a second.It only works in some cases though.