ES 5520C error C3A0 Magenta toner sensor at upper limit

**Desert Rat** · 02-12-2016

Not real familiar with the Toshiba color machines. I have only worked on a couple of these 5520's.
I do work on a number of the black and white Toshiba's.
The customer is still able to make black and white copies and prints. But no color.
I read the section for the auto sensor adjust. It looks like the dev mix has to replaced to use this
program? I was hoping it was like the b/w's and I could just adjust the voltage back to spec.

This is a new customer for me and I have not seen or worked on this unit til now. There was not
a service log with the machine so I have no history of whats been done. I did see that the developer
for this model at Precision Roller is $545.00. And the sensor is only $35.00.

After reading the adjustment it also sounds like if I wait long enough the auto toner adjust program will
act like the b/w and just display the voltage. Am I reading this correctly?
I read a different post by blackcat and someone posted that they were adding toner manually, I have done this
on some BizHub colors but always re-run the toner set program so it would track the new concentration level.

Where's a good place to start on this code?

Thanks

DR

**gliderider** · 02-12-2016

Originally Posted by Desert Rat

Not real familiar with the Toshiba color machines. I have only worked on a couple of these 5520's.
I do work on a number of the black and white Toshiba's.
The customer is still able to make black and white copies and prints. But no color.
I read the section for the auto sensor adjust. It looks like the dev mix has to replaced to use this
program? I was hoping it was like the b/w's and I could just adjust the voltage back to spec.

This is a new customer for me and I have not seen or worked on this unit til now. There was not
a service log with the machine so I have no history of whats been done. I did see that the developer
for this model at Precision Roller is $545.00. And the sensor is only $35.00.

After reading the adjustment it also sounds like if I wait long enough the auto toner adjust program will
act like the b/w and just display the voltage. Am I reading this correctly?
I read a different post by blackcat and someone posted that they were adding toner manually, I have done this
on some BizHub colors but always re-run the toner set program so it would track the new concentration level.

Where's a good place to start on this code?

Thanks

DR

Hi: You didn't say if you had a service manual or not. If not I would highly recommend it as these can be tough to work on without one. The error you listed is pointing at the magenta ATS sensor, but I would look at my connectors first. Also I would print out a PM support page and look at where all the PM items are at in their life cycle. Power up in START 9 and key in 103 or use the "1048" method if your familiar with it. You could always swap the ATS sensor with one of the others and see if the problem follows that ATS sensor. Then at least you will know if the problem lies somewhere else. I would not spend the money on a shot of developer until I verified that there wasn't sufficient magenta developer in the developer unit. ie a poorly developed brush.

Andrew

**blackcat4866** · 02-13-2016

I think I would approach it a little differently. If you've got any of those irritating diagonal void areas on the developing roller, you're probably going to need the developer change. This series of machines has self replenishing developing. That is, if it is reasonably close to the correct developer density, a small amount of developer is introduced with the toner. If it's too far out of specs though, it won't add toner, and won't self replenish. Consequently there is no specific yield on the developer starter. We've had developer survive 1M copies.

You do not mention the copy counts, but if getting up there in count, like 1M color clicks, you may have worn out the developing roller. Check for any slop in the rear developer bearing and spacer.

Also you can get a buildup of hard developer over the toner sensor face. There are two ways to address that:
1) you can give the developing unit a rap with the back of your screwdriver, to dislodge the crust.
2) you can remove the toner sensor and poke around in the oriface.
Keep in mind that these toner sensors are sensitive to static discharge, so don't vacuum too close to that toner sensor.
The error may clear once the crust is dislodged, and it may replenish the developer.

This machine is a little unusual in the method it takes developer. You'll definitely want to read the manual. It's not like any other machine I know. So you'll get the developing unit out, vacuum out the magenta developing unit, re-install the developing unit, remove the hopper assembly, insert the developer cartridge in place of the hopper, run the developer insertion/stir, re-install the hopper, and perform the color calibration.

You'll have a lot of questions once you get into this. =^..^=

**Desert Rat** · 02-14-2016

Thank you both for the replies. Yes I do have the manual, that is why I was asking about the developer replenishment procedure.
And yes Blackcat, I'm sure I will have more questions. Starting with the connectors is as good a place as any to start. And I will
check for crust and swap the sensor with another unit.
I'm a little un sure of this customers ability to pay so I am going to go slow.

Thanks

DR

**blackcat4866** · 02-14-2016

Originally Posted by Desert Rat

Thank you both for the replies. Yes I do have the manual, that is why I was asking about the developer replenishment procedure.
And yes Blackcat, I'm sure I will have more questions. Starting with the connectors is as good a place as any to start. And I will
check for crust and swap the sensor with another unit.
I'm a little un sure of this customers ability to pay so I am going to go slow.

Thanks

DR

Yes it's a good idea to take it slow if there's any risk of non-payment.

Getting the developing unit out of the machine is a little tricky:

1) Open the top paper tray and two screws release the front panel.
2) Follow the instructions on the sticker on the front to remove the EPU only, not the TBU and EPU. The primary belt will remain in the main body. It is relatively common for the drum shafts to stick to the drum bearings making the imaging drawer very difficult to remove. There have been many times that I thought I was going to rip off the purple handles. If it is sticky, apply some conductive grease to the drum shafts.
3) The drum units lift out the top.
4) At the rear of the imaging drawer, release the metal crosspiece over the developing unit. It will swivel up to the front and out of the way. It is not necessary to remove it.
5) Remove the hopper assembly. There are about 10 plastic snaps from the rear. It will not come loose all at once. It fits snugly. Disconnect the four hopper sensors. You'll start at one end, and gradually release snaps.
6) The connector for the toner sensor is seen from the front at each developing unit. It's deeply recessed, so there's a plastic jig to hold and fit the connector for each dev unit. It pulls straight out.
7) There's a metal retaining bracket visible through the front of the drawer, to release each developing unit. You'll need your long magnetic screwdriver, and a set of hemostats to remove, and refit the bracket.
8) Slide the developing unit to the front as far as it will go. Raise the rear of the desired developing unit to get it out, to the rear. It's easy to bend the bias contacts at the rear, so be careful not to bend them.

To reassemble, just do the same things in reverse.
=^..^=

**Desert Rat** · 02-15-2016

Blackcat,
After reading your post it made me remember I have done this once before on another unit.
It was a year ago or more. As I recall some of the copies had a barber pole stripe going through
the image.
I will review the svc manual before going out on this call.

Gliderider, please chime in if you can think of anything. I need all the
advice I can garner.

Thanks
I'll post results

DR

**gliderider** · 02-15-2016

Hi:

I agree with everything Blackcat has posted. He is spot on. Another thing to be aware of is if you have to remove either the k or y dev units.
The cross members that are lifted up for just those two colors have a drum thermistor attached to them towards the front. Be careful not to
deform them as you open and close the cross member. They should just contact the drum as the cross member is closed.