Drum light comes on, but the drum is perfectly fine

Only time will tell. Any way you can stiffen up the drums movements so as to cut down on excess travel that may cause the issue?

There is a chip on the cartridge, so no way to reset.

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

Many drums have a chip with a lifecycle. You may need to replace the chip if you dont want to replace the drum.

with the front cover still open press "clear/back." it will ask if you are replacing the drum unit. press the up arrow to indicate yes. wait till it says accepted and then close front cover

We have just changed our drum unit but the drum light is still flashing. The printer is printing though. Any suggestions?

you have to to reset your drum. first open the front cover then hold the go button and power on your printer . you will see that all the light will glow release the go button and close the front cover now your printer will work perfectly.

The clothes are getting pinched between the drum and the housing. Check the gasket(s) where the drum turns on the housing at the front and back. If the gasket is worn there is a small gap that clothes can get pulled into. The marks are from the worn metal. Lighter weight clothes are more likely to get caught. The gaskets can be replaced by removing the drum.

The problem is that the revolving drum doesn't contact the OPC drum proberly. You have to open the left side off the machine and replace the little white gear on the shaft that drive revolving drum. The gear has "jumped"one step and the revolving drum isn't parallell to the OPC drum. I fixed my 2840 last night it takes some time but now it works perfect.

It sounds to me that your maint counter needs to be reset. 24-7 will reset drum. Let me know if you need help getting into the simulation.

it's likely that your drum/toner delivery system is out of adjustment. That drum should come out nice and easy, so perhaps, during the extraction phase, something snapped? It's possible. Is it still under warranty, by chance? That may be the only way to get it back on it's feet, since opening up this unit, and replacing all the potentially damaged components, could be quite intensive. Got backup?