Konica 7020 error f-26-2

[Rigger]

I need to know if there is a soft switch/dipswitch to clear this code, (or what). I changed dev. and now the code won't go away, (it worked ok before except for faded copies). I cleaned the plugs and sensors on the dev. unit and drum unit. I even installed another dev. section but the code pops up immediately.
Any suggestions?
Rigger

[Luther]

Clean the sensor in the drum unit, chances are thats why you had faded copies in the 1st place,that sensor works with the tds sensor in the dv unit to add toner,good luck

[173545]

Possibly a clogged toner supply unit.

[Rigger]

I looked for "THE SENSOR" in the drum unit and cleaned what I could find but to no avail. Where exactly is the sensor. Copier had over 200k on the dev in it.
Thanks for the suggestions. I service most level 1 machines and have excelent success most of the time, (been doin' it since 1974). Konicas seem to be somewhat unique. I used to sell Konicas in the era of 1290/1590 etc.... Even then procedures were different and parts more expensive.

[dogsbody]

Under the cleaning blade, centre of the drum unit - if its dirty when you run L-detect you get a 0006 error or something along those lines.

[Rigger]

Thanks for the help. Yesterday before I checked this forum again I decided to change drum units from a known good machine. That solved the problem so I took the old drum unit apart and cleaned it out thoroughly. I then saw the white sensor between the pick fingers. It didn't look dirty. Funny, the machine worked OK before I changed developer, (the drum unit was still exactly as it was before dev change). But, sure enough, I put the "CLEAN" old drum unit in and "Voila", she's runnin' fine. You were right, the L detect code was 0006. After changing drum unit L detect ran quit a while and OK came up.
Thanks to all of you.