Canon C7260 color registration off

[nathicana]

I am trying to resolve a Canon C7260 color registration problem. Auto correct color mismatch fails every time. It started out as the magenta being off visibly on a pg6 print. Alarm codes 340001, 340002, 340003 were present but mostly 340002. System software is up to date.

Replaced registration patch detection assembly and copy quality went bad for some reason. Hard to decipher which number to enter as the new sensor alpha value. Going to call Canon to clarify that.

Black is ok but colors are now faded with magenta and yellow developer units depleted toward rear as though not enough developer but no dumping of carrier noticed.

I attempted to attach a pg10 that shows the initial condition with a white space between the black and magenta bar.

[teckat]

Make sure I don't have a
broken \ cracked drum drive gear on Magenta Drum end.

[nathicana]

I checked the magenta drum gear, it appeared not cracked or broken. The yellow drum and developer fixed the problem. Yellow had not been filling in toward the rear of the machine so patch detection sensor must have been getting an unsuitable reading. Magenta was previously not filling in at the rear but had come back on its own. It seemed to be the combination of replacing the patch detection sensor assembly and ensuring a good image. I also clarified the correct number to enter for the sensor alpha value.

[teckat]

I checked the magenta drum gear, it appeared not cracked or broken. The yellow drum and developer fixed the problem. Yellow had not been filling in toward the rear of the machine so patch detection sensor must have been getting an unsuitable reading. Magenta was previously not filling in at the rear but had come back on its own. It seemed to be the combination of replacing the patch detection sensor assembly and ensuring a good image. I also clarified the correct number to enter for the sensor alpha value.

Observation & Good Work :-)) pays off in the end