[Error Code] irc5180 e000020-04b3 now e0000020-0434

[copi2day]

I have been working on ir c5180 that is driving me crazy. first time they were complaining about fuzzy copies.(color registration off) I cleaned copier and calibrated color registration and gradation. about a month later they say color registration has been erratic--comes and goes-- then they get a E000020-04b3 code. I replaced the transfer ass'y for the color registration thinking it must be slipping and the black drum unit for the code. Then I get the e000020-0434. Thinking the new black unit is bad I overnight another black unit--same result. I see the toner bands on the transfer unit(black kinda weak looking-didn't realize that was a clue at that time) so I ordered the salt sensor. Still same problem. I swapped the black and cyan drum units to discover solid cyan on transfer belt during warm up. Appears to me the charge roller would not be getting voltage but the service manual says the copier uses charge current to verify a drum unit is installed. Does any body have suggestions for this. I hate to keep buying parts when I am merely chasing my tail.
Thanks

[canonbundy]

Re: irc5180 e000020-04b3 now e0000020-0434

Hope this helps.

Symptom
An E020-0434 Error Code is Occurring at Start Up.

Cause
This was a hard failure of the Black Developing Unit. The black image was missing from the ITB Belt. All other colours were present. The technician swapped the Black Drum, the Black Laser, the Black HVT2 and the DC Controller to no avail. The technician then pulled out the black drum and marked all the drive gears on the back to see if they turned during initial rotation. The gear for the developing cylinder was not turning.

Note:
The Relay/Driver PCB (FM2-6299-000) and the Developer Drive Motor (FK2-2518-000) control the movement of the Developing Cylinder.

Action
In this case, replacing the Relay/Driver PCB (FM2-6299-000) resolved the issue.

[copi2day]

Re: irc5180 e000020-04b3 now e0000020-0434

Hope this helps.SymptomAn E020-0434 Error Code is Occurring at Start Up.CauseThis was a hard failure of the Black Developing Unit. The black image was missing from the ITB Belt. All other colours were present. The technician swapped the Black Drum, the Black Laser, the Black HVT2 and the DC Controller to no avail. The technician then pulled out the black drum and marked all the drive gears on the back to see if they turned during initial rotation. The gear for the developing cylinder was not turning.Note:The Relay/Driver PCB (FM2-6299-000) and the Developer Drive Motor (FK2-2518-000) control the movement of the Developing Cylinder.ActionIn this case, replacing the Relay/Driver PCB (FM2-6299-000) resolved the issue.

I saw that on the forum earlier so I had marked the couplers(drive gears) on the drum/developer unit to see if they were turning and they are. Sorry I forgot to mention that in the original post. Thanks for the input.When I traded spots with the black and cyan units the cyan unit was laying solid blue on the transfer. This also lets me know the motors are turning good. The black has apparently run out of toner in the developer mix due to laying down solid color during warmup. Then there is not enough black for the sensor to read when time to do so. I may try high voltage units next??????I won't be able to try til after Thanksgiving break.