Message is to re-seat toner, so I remove it and put it back, then it works fine. After a while the same message appears. It is not always the same color. I have removed all Imaging units as well as the fuser and transfer unit, cleaned it all up, and put it back together. Error message continues to pop up from time to time. What is the problem?
The problem is a crazy design in the printer itself! I've now found a reliable fix for this problem which is relatively easy to carry out. You will find the details of how to do it here :
www.michelsplace
Michel's solution works! I had just bought my 7300N used and everything was great except I kept getting a "cyan toner is unseated" error message. I mean, I would run a test page and then I'd get the error...like every other page. I read through the other suggestions on this page and I tried the "crazy" suggestion of removing the foam on the flag and putting sticky tack on the side of the flags and my problem is solved. I've so far printed multiple pages with no trouble. So go to: http://www.michelsplace.co.uk/xerox-7300.html Michel mentions that the foam you take off is to sound deaden when the flags hit, but I can't hear anything different over the general hum of the printer, so I'm happy.
First thing you should try is the toner cartridge. Second, is to replace the toner Sensor Flags. Thrid, is to replace the Toner Sensor Board. Fourth, is to replace the Engine controller Board.
I usually fix this issue by replacing the Flags... if not I try the Sensor Board (usually doesn't work), and then I replace the Engine Controller Board as a last resort.
Replacing the FLAGS is the BEST solution. I have posted a video tutorial on YouTube on how to replace them. Search for Xerox 7300 Flag replacement or something and you'll see me and my video.
This is a VERY COMMON issue. But is simple to fix/troubleshoot. Good Luck.
We have found that the toner sensor flags are magnetic, and may loos their magnetism over time. When we replaced the sensor flags problem went away. Note flags are located on the top cover assy.
TRY FIRST (Solutions without parts):
1. Toner cartridge sensor is dislodged or stuck. - Reseat and verify movement of the toner cartridge sensor. It may be necessary to remove the flag and sand the pivot shaft and smooth to provide free movement. 2. Toner is packed in the sensor window of the toner cartridge. - Remove toner cartridge and Image unit together as an assembly and tap on a table or counter to clear toner sensor window. 3. toner sensor magnets are not properly seated. - Verify the toner sensor magnets are properly seated in the actuators.
TROUBLESHOOTING TIPS AND HINTS:
Test the toner sensors in service diagnostics. Inspect the Toner Sensor Flags for smooth movement. It may be necessary to remove the flag and sand the pivot shafts smooth to provide free movement. Inspect the wiring harness from the toner sensor board to the engine control board. Use service diagnostics to test the Imaging unit drive motor. Remove the imaging unit keys from the back of the imaging unit and swap the imaging unit and toner with another color.
CAUSE:
The problem has been isolated to the Top Cover Inner Frame molding that holds the toner sensor flags for each color. The Top Cover Inner Frame molding has too much variation where the toner sensor flags are seated causing the flags to bounce more than the algorithm can handle. This creates a false error of missing toner cartridges.
I GOT THE SOLUTIONNN SEND ME SOME MONEY IF U LIKE IT
U KNOW THE LENS CLEANER THAT COMES WITH THE TONERS?
OPEN THE PACK USE A PIECE OF THAT PACK TO COVER THE TOP OF THE TONER MAGNET AND CHECK IT OUT
I watched the video replaced the sensor flags and it repaired the cyan and magenta reseat error message. However, now I getting the message for the black toner and cannot clear it. I was not having a problem with the black before. Please help.
So should replacing the sensor board is the best solution?
Fixed! 
Did not fix.
Replaced the Print Engine Control Board,
1,704 views
Usually answered in minutes!
Message is to re-seat toner
, so I remove it and put it back, then it works fine. After a while the same message appears. It is not always the same color. I have removed all Imaging units as well as the fuser and transfer unit, cleaned it all up, and put it back together. Error message continues to pop up
from time to time. What is the problem?
The guru appears right.- when i run a diagnostic the tonor sensor is going nuts! Is there a long term fix ie replace the top?
How can i get into the service diagnostics made ?
How can i get into the Service Diagnostics mode ?
So shold I replace the sensor braod ?
I have been fighting this issue for a while. There does not appear to be one specific fix. I have heard everything from replacing the top cover, the flags, belt, build up around the auger in the cart, sensor board, the moon phase, you name it. I have yet to see a final fix.
I just had a tech in on it again and he checked the sensor flags in service diagnostic mode and they seem to be working, he cleaned the gears that drive the toner cart lift (they are below the belt) cleaned and vacumed it out, I am still getting the error on occasion but it's better.Â
 BTW Anyone know how to get into the Service Diagnostics mode?
We have a xerox phaser 7300 that we do not get service for anymore so I'm trying to keep it running on my own. We got the "reseat magenta toner" message and it won't work to even print in just black and white so we're screwed. I wish I could keep it working. I cleaned it out and put in a new imaging unit since we had one in stock, and that didn't help. I turned it off for five minutes to reset it and it still doesn't work. Please help!
I recently got a tech into to look at mine - it has all the same problems you describe: no magenta, reseat magenta, and this message sometimes swaps to different colors. My tech cleaned it very thoroughly - making sure the sensor flags moved freely, getting all the tonor out of every corner. My sensor flag diagnostic also shows one flag going wild. We swapped around the cartridges. Sometimes the printer works fine and prints beautifully but then the problem comes back again within ten minutes of being powered up. I tried the glasspaper on metal option - it worked occasionally but since the problem is intermittent and comes on the tech suggested he thinks it is not toner but overheating on the engine control board. Could this also be an option?? What are the types of costs involved in new sensor flags or a new engine control board - can they be installed by an amateur
×