Xerox 7760 displaying Magenta Toner Empty on a new toner cartridge. I've gone through 2 full toners and even tried replacing the imaging unit. It briefly shows full then goes back to empty after the printer goes through its cycle. Anyone have any ideas?

Did you remove all paper and stickies? just a spec of dust can block a contact to the chip on the cartridge.

Between the LED rasterizers (four of them, one for each of CMY & K), there are rockers with a small but powerful magnet. When the lid is closed, the magnet will touch the top of the toner cartridge, which in turn, has a magnet on a rod that goes up and down with the rollers when the toner is churned in the cartridge. If the toner magnet is not in the position it is supposed to be (you can check it's position with a hand held magnet), the sensor will falsely interpret that no cartridge is present. You may need to replace the toner cartridge, or if you have more time than money, empty the toner cartridge into a clean vessel, disassemble the cartridge, fix the magnet-on-a-wire assembly, reassemble the cartridge, and replace the toner from the holding vessel. Or, just buy a new cartridge.
On the other hand, I've noticed the rocker switches get sticky in lower temperatures (I keep my 2135 in the garage). Maybe a shot of WD40 on the rocker would help, but to do that, you'll need to remove the lid. It's not too hard, there's only about 9 screws, after removing the back panel (another 4 or 5 screws), After a few more screws around the toner sensor panel (a PCB), you disconnect some quick-disconnect switches, and then you can see the rockers (the actual switches are opto-electrical components on the PCB, you might clean them with alcohol, but they are discrete packages that can't be repaired).
This is a major flaw in the Xerox 2135 (probably persists in the 7300 series as well) and the OKI 9200/9300 series upon which the 2135 is based. There's way too much that can go wrong, but the killer is that nothing except the sensor is failing. Very frustrating!

That is a magenta toner empty message, either the magenta cartridge is empty or there is an issue with the magenta toner dispensing.

Hi armaskopljak:
You have replaced the toner cartridge but you still have to replace the imaging unit which is the drom that the toner cartridge attaches to.
Toner Cartridge OK, Low, Empty When 15,000
(high-capacity cartridge) or
7,500 (standard-capacity
cartridge) pages are
printed (5% print density).
Imaging Units At/Near end-of-life When 30,000 pages are
printed out or when the
pixel counts are
exceeded.
A fuse in the new
imaging unit will blow
upon installation,
resetting the counter.
Verify color calibration. Clean lenses.

Xerox Part Numbers

Toner Cartridges:
Standard Capacity Yellow 016-1975-00
Standard Capacity Magenta 016-1974-00
‘ Standard Capacity Cyan 016-1973-00
Standard Capacity Black 016-1976-00
High Capacity Yellow 016-1979-00
High Capacity Magenta 016-1978-00
High Capacity Cyan 016-1977-00
High Capacity Black 016-1980-00

Imaging Units
Cyan 016-1993-00
Magenta 016-1994-00
Yellow 016-1995-00
Black 016-1996-00
Hope this helps

Hi rmcday: Here your problem. The imaging unit creates the image using an electro-photo process. The imaging unit consists of the following: ■ An OPC Drum ■ Waste Toner Assembly ■ Charge Roller Assembly 9.0 Consumables, Routine Maintenance Items and Options Item Life based on 5% coverage Part No. Replaceable by Black Standard Toner Cartridge Black High capacity 3,000 7,000 106R00679 106R00684 User replaceable Cyan Standard Toner Cartridge Cyan High capacity 2,000 5,000 106R00676 106R00680 User replaceable Yellow Standard Toner Cartridge Yellow High capacity 2,000 5,000 106R00678 106R00682 User replaceable Magenta Standard Toner Cartridge Magenta High capacity 2,000 5,000 106R00677 106R00681 User replaceable Imaging Unit 50,000 images 108R00593 User replaceable Transfer Belt 50,000 images 108R00594 User replaceable 500-Sheet Feeder N/A 119650600 Waste Toner Cartridge 3,000 to 5,000 pages (color 5%) 106R00683 User replaceable. Your imaging unit may have exeeded it life of 50,000 pages and will need to be replaced. Hope this helps

Check out the suggestions on my web page article :

http://michelsplace

You need to check with Xerox , ther is some toner that was manufactured last year (2008) that was defective

the phone number for xerox support is 503-682-7377

When you take the toner cartridge off the imaging unit, is there magenta toner in the open slot of the IU? Assuming that there is nothing wrong with the toner cartridge, you are possibly looking at a bad engine control board.

You need to manually reset the CRU counter in the service menu to reset the toner count. This is designed so the xerox tech can come in and get paid for work. What you do is the following:
Enter the service mode by turning the machine off....then hold the (i) button and (<) arrow button simultaniously while turning the machine on. Then go down to nvram access enter menu, then go to CRU menu. Then go to the Toner CRU count menu, then select the toner you wish to reset and allow the machine to reset.
IF you need any parts feel free to come to my store
Andrew www.Getthatpart.com

Could be many things...depends on the exact nature of the problem. Where the machine states "Invalid Toner" either the machine itself or the toner cartridge may be the wrong "region". i.e. has been sold in the wrong country..the initial toners will work but as soon as you put new ones in they will give this message. If the machine is still displaying "out of toner" then either the toner cart itself is faulty (assuming they are original Xerox carts) or the Image Unit could be faulty (the bit they plug into). Failing that, it will be a faulty Main PCB. The Toners on these have a crum chip, so they cannot be just re-filled and some that may seem "compatable" will not work either.....