Toshiba E Studio 4520c C970

[Contagious]

Hi, I am attempting to get an E Studio 4520c printing again, however cannot seem to find the cause.

Apologies, this is my first time attempting to fix a printer like this and am still quite naive, but eager learn

Background:

• It has done 800,000 pages, purchased from a sport centre.
• Demonstrated working colour, however had streaks. (Black printed perfectly).
• Colour stopped working after transport, probably was the magenta electrode grid broken end block as pointed out here: http://www.copytechnet.com/forums/to...code-c970.html
  • Colleague did not know this at the time, somehow managed to disabled colour printing and get black to print (this all we needed at the time).
  • If someone printed in colour, would spit c970 and would need to reset the printer to get it printing in black and white.
  • The broken block end was "fixed" using a macgyver approach using a nail and a drill? Would this be a problem?

[C970] High-voltage transformer abnormality
(1) Is the main charger installed securely?
All of these appear to be latched on correctly, have used a voltage meter to ensure that corona grid and need electrode are not shorting in any developer unit.


(2) Check if the spring of high-voltage supply contact point is deformed.
Not quite sure what it means by this, assuming its the connections in Figure 1 (see bellow).
Have attempted to bend the contact points up to ensure they are getting connected.


(3) Check if the needle electrode is broken or the main charger grid is deformed.
Not broken an any of the developer units, minus the magenta broken end block that was "fixed" using a nail and drill. Probably need to order a new one.


(4) Check if any foreign matter is on the needle electrode or main charger grid.

• We tried cleaning them with alcohol, however not sure how to do this property?
  
• There is one minor minor scuff on one of the Corona grids.

Figure 1: HVT Connections to Developer Unit:
IMG_20170828_112059.jpg


Debugging:

1. Hold down 0 + 5, type in 201, 202, 203, 204 and click start, each time results in C970
   • Take out developer units, and test one at a time using the above, still results in C970
   • Take out main charger, still results in C970
   • Is this the correct way of individually testing each develop unit?
   
   
2. Test contact points of main charger, does not appear to be shorting out.
3. Force start (0 + 6) spits a C970

Questions:

1. Are there any other ways to determine the root cause and or narrow it down? Or which develop unit is causing the issue.
2. How would one determine if the high voltage transformer is broken?
3. How sensitive is the main charger grid?

Any help would be appreciated

[djbass]

Re: Toshiba E Studio 4520c C970

Questions:

1. Are there any other ways to determine the root cause and or narrow it down? Or which develop unit is causing the issue.
2. How would one determine if the high voltage transformer is broken?
3. How sensitive is the main charger grid?

Any help would be appreciated

1. In my experience the process unit with the fault will usually have a thick coating of toner on the drum when you inspect the unit.
2. If I recall, you can try unplugging each connector for each colour on the HVT board to try and isolate which one is causing the fault.
3. Not very sensitive so long as it is seated correctly, also make sure it is not too dirty or corroded.

[Phil B.]

Re: Toshiba E Studio 4520c C970

Hi, I am attempting to get an E Studio 4520c printing again, however cannot seem to find the cause.

Apologies, this is my first time attempting to fix a printer like this and am still quite naive, but eager learn

Background:

• It has done 800,000 pages, purchased from a sport centre.
• Demonstrated working colour, however had streaks. (Black printed perfectly).
• Colour stopped working after transport, probably was the magenta electrode grid broken end block as pointed out here: http://www.copytechnet.com/forums/to...code-c970.html
  • Colleague did not know this at the time, somehow managed to disabled colour printing and get black to print (this all we needed at the time).
  • If someone printed in colour, would spit c970 and would need to reset the printer to get it printing in black and white.
  • The broken block end was "fixed" using a macgyver approach using a nail and a drill? Would this be a problem?
  
  

[C970] High-voltage transformer abnormality
(1) Is the main charger installed securely?
All of these appear to be latched on correctly, have used a voltage meter to ensure that corona grid and need electrode are not shorting in any developer unit.


(2) Check if the spring of high-voltage supply contact point is deformed.
Not quite sure what it means by this, assuming its the connections in Figure 1 (see bellow).
Have attempted to bend the contact points up to ensure they are getting connected.


(3) Check if the needle electrode is broken or the main charger grid is deformed.
Not broken an any of the developer units, minus the magenta broken end block that was "fixed" using a nail and drill. Probably need to order a new one.


(4) Check if any foreign matter is on the needle electrode or main charger grid.

• We tried cleaning them with alcohol, however not sure how to do this property?
  
• There is one minor minor scuff on one of the Corona grids.

Figure 1: HVT Connections to Developer Unit:
[ATTACH=CONFIG]37439[/ATTACH]


Debugging:

1. Hold down 0 + 5, type in 201, 202, 203, 204 and click start, each time results in C970
   • Take out developer units, and test one at a time using the above, still results in C970
   • Take out main charger, still results in C970
   • Is this the correct way of individually testing each develop unit?
   
   
2. Test contact points of main charger, does not appear to be shorting out.
3. Force start (0 + 6) spits a C970

Questions:

1. Are there any other ways to determine the root cause and or narrow it down? Or which develop unit is causing the issue.
2. How would one determine if the high voltage transformer is broken?
3. How sensitive is the main charger grid?

Any help would be appreciated

Wow a nail in the charge grid? are you sure it is not discharging thru that nail?

[blackcat4866]

Re: Toshiba E Studio 4520c C970

I usually just visually inspect each charger for obvious flaws. I usually see:

1) broken off post on the rear block.
2) broken seesaw (scorotron and grid tensioner at the front). It will break at the scorotron spring mount, or the swivel points, or where the grid attaches.

In either case the scorotron or grid sags until it touches the drum. Yes theoretically the appropriately colored developer will deplete faster than it can replenish. Start out with the MacGuyvered one. =^..^=

[Contagous]

Re: Toshiba E Studio 4520c C970

Appeciated the replies

1. In my experience the process unit with the fault will usually have a thick coating of toner on the drum when you inspect the unit.

Thanks, looks like it is the cyan process unit (not the MacGuyvered one :P ), had to turn it on twice to get a coat of toner:

IMG_20170829_191049.jpg

1. I tried switching the main charger with one from a different unit, however the cyan still gets coated with toaner. Does that mean it's probally not the main charger, but something else?
2. The cyans magnetic roller, seems to also be coated with thich toaner - the other colours do not have this. Is this normal? Also all of the magnetic rollers are silver, should they be black?

3. Not very sensitive so long as it is seated correctly, also make sure it is not too dirty or corroded.

Did not see any corrosion, and look quite shiny and newish - some tiny kinks.

In either case the scorotron or grid sags until it touches the drum. Yes theoretically the appropriately colored developer will deplete faster than it can replenish. Start out with the MacGuyvered one. =^..^=

Thanks , None of them appear to be sagging. But will probably need to get a new one to replace the MacGuivered one :P

Wow a nail in the charge grid? are you sure it is not discharging thru that nail?

Thanks, does not seem to be shorting, when I use a tester. But probably should replace it

[Contagious]

Re: Toshiba E Studio 4520c C970

Thank you all for your replies

Looks like it was the MacGyvered nail.. Changed the nail with a with plastic MacGuyvered rod and the printer starts up

Threw us off, since we still got c970 when we took it out and it the toaner was coating the cyan instead of the MacGuyvered one (magenta).

Thanks again

[didi2005]

Re: Toshiba E Studio 4520c C970

Most of the time is C970 is due to main charger issue such as

1. TERM-CHARGR-MAIN-RER hook break
2. SEESAW-GRID-ELCTRD hook break

[blackcat4866]

Re: Toshiba E Studio 4520c C970

Congratulations on your success. =^..^=