If the manuals don't help, it is time to arrange for service. Get quotes as sometimes repair/service is more than a new printer.
Bob
Dear Cnet Forum Dell Members
I hope very much someone may be in a position to assist further?
I am trying to clear error code: 077-900 open rear cover Remove paper jam. This error message has remained after a recent jam.
I am fairly certain that there are no fragments left behind after removing the piece - however; I am uncertain as to how I should actually go about removing the toner/drum unit and to ensure this is the case? and if this does not clear the error - how best to proceed from that stage?
I did perform a recommended diagnostics being: "To test the registration sensor, you need to enter Customer Diagnosis mode on the printer. To do this: 1. Power off the printer 2. Press and hold the UP and DN arrow keys while powering on the printer; the buttons may be released when the LCD indicates "Diagnosing". 3. LCD should indicate "Customer Mode" and "ESS Diag" (or something similar). 4. Press the DN arrow to display "IOT Diag"; press the ENTER button. 5. LCD should indicate "IOT Diag" and "Digital Input"; press the ENTER button. 6. Press the UP/DN buttons until the desired DI-xx is shown, then press the ENTER button to execute the test. The test we want to run is the Regi-Sensor test -- DI-3. Press the up arrow until the LCD indicates "DI-3 OFF" then press the enter button. The LCD should now indicate "DI-3 L 0"."
The result indicated: "DI-3 L 0".
I have tried removing toner cartridges and rod cleaning.
I have tried a hard reset of the printer.
I have not been able to ascertain where the registration sensor is located and where paper enters the sensor area?
If possible: an image of what I should be looking for would be beyond awesome! I am a complete novice at this! [And admittedly: WAY OUT OF MY LEAGUE HERE & SCARED TO DEATH!]
I was able to read an old post that suggested you could: "toggle the regi-sensor positioner and get the display to change from L to H to L, continuously, then you've cleared the jam. The number will increment indicating how many times you've cycled the positioner. If you need better access into this area, remove the Toner/Drum carts and set them aside."
This is something I am yet to attempt as I am oblivious as to how to remove the Toner/Drum cart...
Any and all advice would be so very deeply appreciated!

Chowhound
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