bizhub 750 drawers 2,3 ,4 out of function

[cristian]

So,
Me and my friend have 3 bizhub 750 machines with the same malfunction : drawers 2,3 and 4 are out of function. In the meantime we have found another 3 bizhub owners who want to sell the machines specifically because of this particular problem.So MINOLTA TECHNICIANS, HELP.Seems that this problem is growing...
Description: paper jam in the vertical conveyance in the paper axis of the 2nd drawer, no matter which drawer(2,3 or 4) I take the paper from. What we have done untill now to solve the problem (error J1704): means that the sensor from the by pass(P36)is not activated in right time after the paper pass from the pre registration clutch.
1.We have change the vertical door, to be able to verify if the door sensors are OK
2. We have change the both 2 vertical conveyance clutches.
3. We have power from another source the 2 clutches.
Without result.
If the motor is not OK we have presume the machine will give us some error codes...
So we have now remain without options, except to change the boards one by one....Seems to not be a mechanical problem, because if we turn manually the motor,the clutches respond OK.
So any sugestions ? Seems to be the most interesting problem, especially due to the fact that my firend warnme that the machines will remain soon 300 K/400 k without paper supply from the drawer 1 and bypass who still working...Could use the external feed box but what about A3 and A4R? So if you have any ideeas ....

[Downunder]

Re: bizhub 750 drawers 2,3 ,4 out of function

There is a previous post here -- have you removed the drum carriage and checked the wires from the drum pick-off pawls' solonoid. They have probably been squashed against the drum bearing and have blown two ICB's on the PRCB - Once you have rectified the wires you will need to either replace the ICBs or a new print control board.

[emujo]

Re: bizhub 750 drawers 2,3 ,4 out of function

There were also some issues with the tray wiring insulation getting exposed and blowing the PCB. This MFP is at least 10 years old...might be time to upgrade..but you might find the external LCT on Ebay. Emujo

[cristian]

Re: bizhub 750 drawers 2,3 ,4 out of function

There is a previous post here -- have you removed the drum carriage and checked the wires from the drum pick-off pawls' solonoid. They have probably been squashed against the drum bearing and have blown two ICB's on the PRCB - Once you have rectified the wires you will need to either replace the ICBs or a new print control board.

Nice work !!!
Indeed the wires were broken...I will measure the ICB s from PRCB ... I have no doubt that s the reason.Thank you.

[cristian]

Re: bizhub 750 drawers 2,3 ,4 out of function

There were also some issues with the tray wiring insulation getting exposed and blowing the PCB. This MFP is at least 10 years old...might be time to upgrade..but you might find the external LCT on Ebay. Emujo

Thank you. I ve checked the wiring... seems to be OK.The external LCT was useful, but is not very confortable for us to see that a quater of the machine is dead ( means the drawers)...

[copyman]

Re: bizhub 750 drawers 2,3 ,4 out of function

Sorry if this is a stupid question but did you go into service mode and "unset" those paper drawers in trouble isolation? Maybe you mentioned it and I missed it. Usually the trays lock out because of numerous jams or a malfunction. For all of those trays to malfunction and lock out at the same time is very unlikely.

Actually tray one is the one I always had problems with, because it has to travel through horizontal transport above tray 2.

Anyway if you have tried all of that then like the others said I would look at a board being bad.

best of luck

[cristian]

Re: bizhub 750 drawers 2,3 ,4 out of function

Sorry if this is a stupid question but did you go into service mode and "unset" those paper drawers in trouble isolation? Maybe you mentioned it and I missed it. Usually the trays lock out because of numerous jams or a malfunction. For all of those trays to malfunction and lock out at the same time is very unlikely.

Actually tray one is the one I always had problems with, because it has to travel through horizontal transport above tray 2.

Anyway if you have tried all of that then like the others said I would look at a board being bad.

best of luck

I have try to "unset" one by one, drawers 2 , 3 and 4, but without succes. Anyway, the movement for drawers 2,3,4 is transmited by a different cinematic chain than the movement for the drawer 1,and we have seen that there it is not a mechanic problem , so must be the board. As soon as i get the board and replace it we will know.I would prefer to use drawer 2 instead of 1 due to the same reason you have mentioned.