Konica 7033 - no image

[schrodingers cat]

Konica 7033 - it scans and then the engine seems to run as usual, but instead of the correct image, it lays down a random-looking layer of about 10% toner. By the looks of the image, I'd guess that the scanned image is not being burned into the eletrostatic drum and the image is a result of whatever static is on the drum instead.

We have tried resetting the machine, with no change in the results.

I'm not a copier technician (my background is in computers and printing presses). If anyone has seen this problem before, I'd love to know what you think, and how expensive a repair might be -- I'm about ready to pitch this machine for something cheaper to own anyway.

Thank you.

[173545]

I have seen a bad front door switch cause this. It's a weak spot on this model.

[CMB]

its starving for toner. check the toner motor on the toner hopper-make sure it turns when running auto add toner. i seen this happen several times and its easy to troubleshoot.

two screws removes the cover. the toner motor is the one closest to you when hopper is swung fully to you right. its on the bottom end.

those motors burn out on the inside. if it doesn't feed toner to the dev unit, copies will be light.

[Mark B]

It is the front door interlock. You can take it apart and clean it with an erase.

[CMB]

all that front door switch is going to do is turn the fuser off or on. nothing to do with light or dark copies.

if so.

please explain. been working on 7033's for 5 years and never had a front door switch cause any issues.

[ebm]

all that front door switch is going to do is turn the fuser off or on. nothing to do with light or dark copies.

if so.

please explain. been working on 7033's for 5 years and never had a front door switch cause any issues.

You must be lucky or better than the rest of us, I guess!!!!

[173545]

Door switch

MS1 (front door interlock) relays 24v to HV1(charge), HV2(T&S) M10 (toner motor), PRDB, M4 (drum motor), M1, and M3 (developer drive motor).

I've replaced or cleaned dozens for copy quality issues and other problems. It might not solve schrodingers cat's problem, but it's the first thing I would check.

[Luther]

I agree I just replaced the switch on friday for a faint image, they tend to cause tons of problems on these machines, have replaced or cleaned at least a dozen over the years, good luck Its also the same interlock as the minolta Di250/350 if you have a parts machine laying around

[dogsbody]

It didn't take me long to learn that Fiery's don't like dodgy door switches either.

[CMB]

that is strange. i have never replaced a door switch on any of my 7033/7040/7045's for any reason. i have replaced many op panel lower covers because the plactic breaks where the switch is attached.

[AusiTech]

that is strange. i have never replaced a door switch on any of my 7033/7040/7045's for any reason. i have replaced many op panel lower covers because the plactic breaks where the switch is attached.

Yep cleaned/replaced heaps!!

[GottaFixEmAll]

The door switches are pricey for what they are .. but they always fix this problem !!!, I don't bother to clean them very often ... but then again I don't see as well as I used to, and my fingers aren't as nimble either ...

Mike

[dogsbody]

that is strange. i have never replaced a door switch on any of my 7033/7040/7045's for any reason. i have replaced many op panel lower covers because the plactic breaks where the switch is attached.

Open some switches on your older machines, you will see what were talking about. There were also modified interlock switch actuators (just a little bit longer).

[GottaFixEmAll]

Well, I used to clean / repair the switches on the older models, unless they were microswitches ... remember the ones on the old KOnica 1803, 2803, 3290,s etc ... the customer would shut the door so hard they'd bend the metal actuator ! and some of teh old mita's that had three separate switches in the interlock !! ... was always fun trying to fold a piece of paper to cheat that switch !!

Believe it or not, I went to school to be an electronics technician .. 26 years ago I answered an ad for a copier technician trainee ... Hmmmhhh ... still doin it .............. must be something in the toner that's addictive ??

Mike

[blackcat4866]

I can't say much of Konica, but I've seen a few Sharps do this. The front door interlock closes intermittently, cutting off the 24vdc to the HVT. If your getting 20 ohms @ the interlock when closed, the main board still sees the door is shut, but not enough current to run the HVT.