My copier has a cf3 code what is that - Minolta EP1030/1030F CS/PRO Copier

CF3 is a ATDC sensor malfunction.The output voltage from sensor is 4,8V or more or less than 0,4V.
Please measurement the voltage across PJ10A 1 on PWBA amd GND:if 4,8V of more change the developer or UN 3;if 0,4V or less change the PWBA.(PWBA = master board.
If you try mixed(add) toner in developer station whit hand(one spoone).
Every time changed the developer must performed the F8.Every time change the OPC drum or OPC cleaning blade perform F5.

Did you recently have the developer changed? Its a code that says that it needs more toner/developer mix. Did you pull out the image unit section, check if it was seated properlydid you install the screw that holds the image unit in. is there toner in the machine, pwr on off then on to clear code, if not mite need to have the image unit developer replaced or the ATDC(Aotomatic Toner Density Control) Sensor, which is under the developing/image unit, very sentative to static electricty!

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