C450 P-31

[B0265]

We have a C450 that pops P-31. It's the first time I have seen this code, have changed sensors PC11/PC36 and black IU.
Have you guys had this before ?

[ni311]

P-31: Black PC Drum Sensor malfunction
1. Perform the faulty sensor check procedure *1.
2. Check the sensor, for which a faulty condition has been checked, for installed position and proper connector connection.
3. Wipe the sensor, for which a faulty condition has been checked, clean of dirt if any.
4. If P-31 persists, change the sensor which was found faulty.
5. Change PWB-MC.

*1: Faulty sensor check procedure
1. Open the Front Door and turn ON the Main Power Switch of the machine.
2. Call the [Sensor Check] screen to the screen by way of Service Mode.
3. Close the Front Door and start [Stabilizer].
4. During the Stabilizer sequence, check to see if the values of the phase detection sensors (Color PC Drum Main/Sub and K PC Drum Main/Sub Sensors) change.
5. A sensor is faulty if its value does not change.

[B0265]

Thanks ni311,
Have already replaced the sensors (PC11/PC36) and was looking for some other suggestions before ordering a new PWB-MC (I'm afraid that would cost more than the machine is worth)
The code pops only when making B/W copies, what's confusing is that you can print in mono without any code.

[ni311]

Try to switch the board from other C450, just to be sure, maybe you're lucky and it's not the PWB-MC, even if it's sounds like a board failure.

[B0265]

No we have tried with the PWB-MC, the complete PWB Box and the K PC Motor (M7) from another machine but the problem remains.
We have also seen the P-31 one during a 150 page print job, but it did reset itself before the print was finished.

[RockETop]

Hey,

Did you ever find a resolution to this. We just got a C351 with the same issue, and we have done all the same things you have done. The techs are whopping their heads against the wall.

Thanks.

Rock

[B0265]

No, it's still unsolved

[mtech]

There is a big stupid looking board on the rear right side of the machine. I think it is called the SYS board. It has a lot of connectors and pretty much nothing else on it except ICP,s. (Internal circuit protectors) They look like little surface mount resistors. I believe there are twelve of them. Check them for an open like a fuse with your meter. If any are open replace the board and hope for the best. Otherwise there are two HV boards in the machine. One for transfer and one for the main charge for each drum. You need to look close because the manual is wrong. (I think Minolta finally admitted this with a bulletin) Try replacing the hv board for the main charge first. I called the SYS board stupid because I ran into lots of issues with these blowing on board fuses and let me tell you if you don't already know, it really sucks replacing HV boards in this machine. Especially the board for transfer which is under the LED unit and comes out through the rear of the machine! Keep us posted and good luck!

[RockETop]

We may have a resolution!

Check the wire harnesses for the color drive sensor and the K drive sensor. We may have switched them. One is blue, one is white.

The machine is running properly at this point.


More later.

[RockETop]

	Quote:			Originally Posted by RockETop
	We may have a resolution! Check the wire harnesses for the color drive sensor and the K drive sensor. We may have switched them. One is blue, one is white. The machine is running properly at this point. More later.

The machine is fixed. Check the sensor's wireharness.