I have a Brother HL-5250, drum light on, not printing

SOURCE: Brother printer HL 5250 DN.

Brother Drum Reset Instructions


The Drum LED continues to blink if the drum counter was not reset when you replaced the drum. To reset the drum follow the instructions below:
Press the cover release button and then open the front cover of the printer.


Press and hold down Go button until all 4 LEDs are lit. Once all 4 LEDs are lit, release the Go button.

Close the front cover.
Make sure that the Drum LED is now off.
Reset the drum counter only when you replaced the drum unit with a new one.

SOURCE: Brother HL-5250 is printing a solid black page

Yes. Remove and re-insert, look for bent contacts.

SOURCE: brother HL 5250 red light flashing

I found this solution on the web-- Hope it helps.

The HL-2070N gets stuck in a toner end-of-life error condition. Perform the following to clear :
With paper loaded, new toner in,

Open front door
Turn off printer
While holding down the GO button, turn printer back on
When all four LEDs light up release GO button. All LEDs will turn off
Press the GO button 2 times. The 3 LEDs (toner, drum, paper) will light up solid
Press the GO button 5 times
Paper light will be blinking
At this point the toner end-of-life condition has been reset. Close front door.
BTW, I got this from Brother Support. Also, just a reminder, timing is important here so don't pause between button presses.

SOURCE: Brother HL-5250 printer toner Light on but Cartridge has Toner it

Try this....
1: Turn off power and remove toner/drum
2: Tape the little spring loaded lever just inside the printer on the upper left hand side in the *DOWN* position! Do not replace drum yet and...
3: Turn power on to printer and let it cycle. Status/Toner lights will come on as usual.
4: Turn off printer, remove tape from lever, replace drum and turn back on.