[Error Code] 4521

[Guest]

Hi,
I have a big problem with my printer bizhub pro 6500 it gives me an error while perform the color registration adjusment the error is C 4521.So i change: the drums unit,coronas,developer,color registration unit,transfer belt and tranfer belt unit, PRCB unit,update firmware and the error won`t stop.Can you help me???

[HORSE]

Are you a Tech or End user?

[printsibiu]

First i was an user an now i`m tech

[HORSE]

Since you say you replaced all those parts I would start back at basics.

1. Is there any other code other than C4521 showing? (ie Gamma failure)
2. Have you tried to panic stop the machine to see the registration marks are on the Transfer belt.
3. Try taping up the Color Registration sensors shutters so that they are definitely open.

[ebm]

Check the space under the dv units where the laser comes through to the drums. I had a machine w/ color registration errors caused by developer stuck to the bottom of the dv unit blocking the laser path to the drum.

[printsibiu]

Before change the transfer belt when i try to make color registration in service mode the code was 2840.When its make adjustment when it start up the code is 4521.
I try to make color registration manual on service mode and the mesage was completed.
I loked up the space before dv unit and laser and it`s ok.
Now i

[HORSE]

C2840 is PGC failure, are you sure the PGC & Registration sensor shutters on the color registration assy are operating? Check ICP 17 on the PRCB is not open. If it is then check the upper cover that you remove to do the Developer change has not trapped the Total counter wires against the frame.

[Stirton.M]

2840 at powerup

Solution ID TAUS0901125EN* Solution Usage 3
Description
C-2840 (C2840)at startup.
Solution
CAUSE: The PGC sensor is malfunctioning.
SOLUTION: Recall Standard Data to Factory Init from the Process Adj screen in Service mode.

solutions for the 4521

C-4521 (C4521) color registration error code.
Solution
CAUSE: It is possible toner or dust is deposited between the color registration sensors, PS8 and PS9, and their outer cover. Simply wiping the sensor will not
resolve the problem.
SOLUTION: Remove the color registration assembly (p/n A03U R7980 0) and inspect the sensors. If toner or dust is deposited between the sensor and its
outer cover, the color registration assembly must be replaced.

I've personally encountered this problem once, it is not easy to see this dust in poor lighting and yes, the unit must be pulled out to inspect it. Replacing the unit is recommended, but if you are careful, you can pop the clear cover off and clean with a q-tip.

The following is this code accompanied by other codes as indicated...
4520 at power up.
with poor copy quality, lines, wrinkles. The transfer belt may mis-track or slide toward one side or the other ("walking" off the rollers).
during color registration adjustment.
after performinga PM.
possibly with C-2714 error code. No image is visible on the transfer belt.
possibly with C-4501, C-4502, C-4503and/or C-4504 error codes.
possibly with C-4521 and/or C-4522 error codes.
Solution
At power up.

CAUSE: Ten (10) pixels of Color registration overlap is detected when comparing to a previous Color Registration adjustment.

SOLUTION: In order to reduce the error occurrence ratio, the following function was added to firmware version 60.
DIPSW 23-1
0 : SC detected condition 10 pixels (Default)
1 : SC detected condition 60 pixels
Notes :
1. To change SC detected condition only, color registration accuracy itself is not change.
2. The purpose of this DIPswitch is to reduce the occurrence ratio. Color registration problem itself cannot be improved.
3. Download and install firmware version 60 if necessary. The latest version firmware or system software is available via the Konica Minolta Download
Selector. Access the Selector from SSD Web Support (CS Expert Support) by clicking on 'Download MSDS, Drivers, Firmware and more'.
Poor copy quality, lines, wrinkles. The transfer belt may mis-track or slide toward one side or the other ("walking" off the rollers).

PROBABLE CAUSES:
1. Upper front bearing falling out of the holderbecause oflack of tension on the upper roller bearings.
Remove and reverse the upper front bearing (p/n 5400 7605 0 listed on page 32, Key 5 in the Parts Manual) so that the bearing flange is outward and/or
slightly re-form the holder in which it sits so that more pressure is applied to the bearing.

2. Tension roller in the Intermediate Transfer Assemblybecoming dislodged, permitting the transfer belt to “walk off” or the upper and lower tension rollers
are not lining up correctly.
Addition of a new spacer at each end of the tension roller prevents the roller from disengaging from the bracket. To accommodate the new spacer, the length
of the roller has been increased slightly and a “D” shape placed on the ends. Refer to attached Bulletin Number 6331 for additional detail. Also, adjusting the
lower tension roller is suggested. Please see the attached document for directions.

3. Gaps between Tension Plate Rear Caulking (p/n 65AA -273 0) and Plate/Rear (p/n 65AA 2625 0E) after maintenance performed on the transfer belt unit.
Set Tension Plate Rear Caulking properly so that no gap exists and firmly fix with screw. See attached files for more information.
Note :Also refer to attached Bulletin Number 6522 which addresses Transfer Belt Sliding.
During color registration adjustment.

CAUSE: Failed color registration sensor PS8 or PS9.

SOLUTION:SwapPS8 and/or PS9. Replace color registration assembly (p/n A03U R7B4 00)
After performinga PM.

CAUSE: The Color Registration adjustment was not performed (bizhub PRO C5500/C5501/C6500/C6501 ).

SOLUTION: Perform the Color Registration adjustment:

1.Enter Service Mode.
2.Select Machine Adjustment.
3.Select Printer Adjustment.
4.Select Color Registration Adjustment and then Start.
5.Exit Service mode.

Possibly with C-2714 error code. No image is visible on the transfer belt.

CAUSE: The first transfer pressure release motor (M19) coupling gear is spring loaded and can become lodged in the back position.

SOLUTION: Release the first transfer pressure release motor (p/n 08AA 8003 0) coupling gear (p/n 65AA 1714 0) so that it springs freely when pressed and
released.

Possibly with C-4501, C-4502, C-4503and/or C-4504 error codes.

PROBABLE CAUSES:
1. Open ICP fuse on the Printer Control Board (PRCB).
Check the continuity of the ICP fuses ICP17, ICP20, and ICP21 with the PRCB out of the machine. You can also carefully check that there is 24V DC on
each side of the fuses while the board is in the machine. Voltage on just one side of the fuse would indicate that the fuse is open and the board needs
replacing (p/n A03U R759 00 - Printer Control Unit).

2. If [09 Writing Init. Pos. Memory] is not performed, the adjustment value is not reset to the initial value. Consequently, adjustment margin is decreased in
some cases.
Whenthe write unit is replaced, clean the dust-proof glass and perform the following adjustments in order:
a. Writing Init Pos. Memory
b. LD Bias Adjustment
c. I/O check mode
d. CD Skew Adjustment
e. Restart Timing Adjustment
f. Color Registration Adjustment
g. Color Registration/Manual (Adjustment)
h. Auto Gamma Adjustment
Note : Please refer to attached Machine Adjustment section taken from the March 2009, Version 2.0 bizhub C6501/C6501P/C65hc/C5501 Service Manual,
Theory of Operation.

Possibly with C-4521 and/or C-4522 error codes.

CAUSE: ICP17 isOPEN on the Printer Control Board. The wiring between the printer control board and the hardware counters may be pinched. If the wire is
shorted to ground, ICP17 on the printer control board will open, resulting in the error code. If the wire is broken internally without shorting, the machine will
function but the counter will not increment.

SOLUTION:Check the wiring between the PRCB and the Total Counter. There might be a short to ground close to the Total Counter. After the short is found
and repaired, replace the PRCB (p/n A03U R759 00).
If the wiring is not damaged, reposition it so that it is secured in the plastic hooks behind the counters. This will keep the wiring from being pinched when the
cover is removed and reinstalled.
It is recommended that all machines be inspected at setup or the next service call to prevent future incidents

[jma676]

Bizhub Pro C6500 - Error Code SC-4521-2840. and other.


This is very easy.--------------------------------------------


C-4521/ 前部色彩对位基线校正中止

C-2840/ 最大浓度控制期间，PGC 传感器 校正失败。

C-4520/ 色彩对位校正中止


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[printsibiu]

Problem solved
ICP 17 was open because wiring between the PRCB and the Total Counter was short in ground see the attach file and another problem was that the
HV DETECTING SENSOR ASSY (p/n A03U R736 00) it was dirty.Luckily for me I have bizhub 6500 and i change detencting sensor one to another.
Thanks and best regards

[HORSE]

I thought that was the problem with the total counter wires trapped and killing ICP17 although I'm a bit confused with that picture since that looks like the back of the process unit. Trapping those wires is usually CC101 because it kills ICP23. Well at least you got it going mate.

[printsibiu]

So it is the back of process unit,who nows for this short ground gives me error 4521 or 2840 when i do color calibration from service mode.

[jma676]

------------------------------------------------------------------------------------
It seems there is a confusion, the cable(Wire) you see in the image Sample on the CARRIAGE SECTION, not belongs to DRPS Cable(wire), maybe belongs to SD1 (Separation claw unit), and maybe this interferes with the Color Registration or Density Control Patch....
much Fantasy?...

But the fact is also that if the ICP17 is blown you should see only one code, as when ICP23 Blown is fixed the C-C101, or another, Check ICP List.
Or just the cable (wire) was in contact with the chassis ground, and the vibration made failures these were random.
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[HORSE]

ICP17

Total counter
Separation claw SD
Color registration sensor shutter SD
IDC sensor shutter SD

That would have to to be the Separation claw SD wires pinched at the back of the process unit, never had that one myself just CC101.

Have to mark that down in my book.

[jma676]