Put in new toner cartridge and printers still shows "TONER EMPTY" . I have reinstalled the toner cartridge 4 times and still have the error message.

Was it a genuine toner cartridge? I bought some aftermarket ink cartridges for my canon. The colour one was OK but the black... The printer kept saying black empty. I put my nearly empty genuine one back and the fault disappeared. Put the copy one in and same result. I bought a genuine black and no problem.

Defective toner pump. call a tech

I would not advise you to refill a toner cartridge becausethe toner powder is very fine and you do not want to breath in this tonerpowder.When the toner cartridge is exhausted or empty then theprinter will not be able to print further documents or the prints will be veryfaint.You may be able to print a few more pages by removing thetoner cartridge and shaking the toner cartridge in a horizontal position a fewtimes and then placing it back into the printer.This will give you an opportunity to print a few more pages and giveyou time to purchase a new toner cartridge for your printer. A cheaperalternative is to purchase a re-manufactured toner cartridge for your modelprinter.A re-manufactured printer cartridge also replaces worn partsas well as refilling with toner powder.

That cartridge have chip, every time you refill the cartridge put a new one chip.

When the toner cartridge is exhausted or empty then theprinter will not be able to print further documents or the prints will be veryfaint. You may be able to print a few more pages by removing thetoner cartridge and shaking the toner cartridge in a horizontal position a fewtimes and then placing it back into the printer. This will give you an opportunity to print a few more pages and giveyou time to purchase a new toner cartridge for your printer. A cheaperalternative is to purchase a re-manufactured toner cartridge for your modelprinter. A re-manufactured printer cartridge also replaces worn partsas well as refilling with toner powder.

1- press MENU #1934 and it show you "TECH"
2- Press MENU, Acept. and it show you "Tech Mode"
3- Press < once. and it show you "NEW CARTRIDGE"
4- Press Acept. [YES].
5- Press Acept
6- Press MENU #1934 to exit "TECH MODE"

Note: Don't wait when press #1934. Do this quick.

If you go here:
http://www.sharpusa.com/files/cop_man_ar287_337_407.pdf
You can download the operation manual for that machine, on page 4-5 they explain how to replace the toner and have pictures showing how.
here is the text on how to replace.

Adding Toner
1 Open the front cover.
2 Pull down the toner hopper lock lever and pull the toner
hopper out slowly until it stops.
3 Tap on the top of the toner cartridge 5 times. Hold the
new toner cartridge vertically and vigorously shake it
up and down about 20 times, then invert the cartridge
and again shake it up and down about 20 times. This will
loosen the toner and allow it to flow more easily into the
toner hopper.
4 Place the new toner cartridge with the tabs in the
notches as shown.
5 Slide the toner cartridge along the guides over the toner
hopper.
6 Hold the toner cartridge with one hand while pulling on
the sealing tape to remove it.
7 Tap on the top of the toner cartridge 5 times to start the
flow of toner into the toner hopper.
l If the toner cartridge was sufficiently shaken as described in step
3, it will take about 50 seconds for the cartridge to empty. Do not
remove the cartridge until it is empty. If not empty, tap on the top
of the cartridge again until empty.
8 Slide the empty toner cartridge back along the guides
and remove it.
l The cartridge opening will be closed as it is moved back along
the guides.
9 Slide the toner hopper into the copier and return the
toner hopper lock lever into place.
10 Close the front cover.
NOTE:
Add only one cartridge of toner.

If you want to use the toner cartridge after the printer decides that it's empty, you can do it by going into the Machine Settings in the menu, and option 8 (at least on my Magicolor 2590MF) says "Toner empty stop?". Just change that to NO, and you're set to go.

1. It tries to pump toner into a reservoir. If it doesn't activate a full sensor for the reservoir, it shows toner low. 2. Take the toner out and shake it hard about 10 times, this will make any settled toner loose, and should solve this. The problem is normally caused by old toner (your supplier might have had it on their shelf for a year or two).