Printer not printing, it said black toner was low...put new one in.....red and blue light staying on

Was the toner 3rd party???? if so go out buy a OEM Konicaminolta Image unit/toner

Btw, I’m available to help over the phone in case u need at https://www.6ya.com/expert/normanj_7893313f0751935f

if you take the toner cart out and look on the right hand side of it, you will notice a little round window, this window lines up with a sensor inside the printer which looks to this window to reflect back off the toner inside (toner still available)
When the toner gets low enough the sensor does not get a signal back and reports that its out of toner hence the red light.....here's the trick.... if you put a small piece of BLACK tape over the window your printer will continue to print until it completely runs out of toner (several 100 more pages)

Hello sir; when you put the new toner in did you remove the seal tape ?

The flashing means that the toner and/or the imaging drum is empty or missing (printing halts on these errors). Lights on steady means low toner.

Maybe the toner is low... According to the manual, a blinking red light:

• A minor error is occurring and
the printer is waiting for the error
to be cleared. When the problem
is cleared, the printer resumes
printing.
• The toner cartridge is low. Order
a new toner cartridge. You can
temporarily improve print quality
by redistributing the toner. See
page 8.3.
• The toner is totally exhausted.
Remove the old toner cartridge
and install a new one. See page
8.4.
• The toner cartridge reached the
end of its life.

From the User Guide:

Black, Cyan, Magenta, and Yellow Supplies Status lights
These lights indicate when a print cartridge is low (the light is on), or empty or missing (the
light blinks). The lights also indicate when a non-HP print cartridge is installed (the light
blinks and the Attention light is on).

If you don't have a User Guide click on the link below and save it for future reference.


2550n User Guide

If this solution has been helpful, please rate it. Thanks!

Trick the thing. Put a piece of black electrical tape on the "eye". (Take cartridge out, on right side there's a small clear hole). Worked for me!

According to the operation manual: If alarm light and data light blink every 5 seconds- TONER LOW (purchase more toner and have it ready when the 'toner empty' is indicated). If alarm light and data light stay lit- TONER EMPTY (replace toner cartrige with new one).

it is printing with this blinking or not?

I can't imagine where toner could possible go from one of these sort of cartridges except on to your paper, I had a customer once with the same request and I found on their letter head that they printed with it had a single band of yellow across it hence excess yellow use,,,,,, Do your print runs of anything contain dark bands/underlines? I guess check to see if white background in any prints has a blueish tinge to it, or possiblly somehow black is running out and it is printing the blacks by mixing the colours (Check black block and text to see if it is really black not heaps dark blue to ensure black toner is operating)

next I'd be questioning if cartridges where brother ones?