MX-7500

[Madnhain]

After Black dev unit, blk developer and drum were replaced, 50-22 fails with code "ENC_TIMEOUT_K"
Skew is WAY off on all colors, no colors align, tried dialing the colors in manually with 50-20, got close but not perfect, 50-22 still fails. Looked at TB, no black patch on 50-22, there was a cyan patch, and the Yellow/Magenta were overlapping almost entirely. Completely gutted the machine, took all components out (DV Units, Process Units, PCT, PS Unit, registration unit, LSU, back cover etc) Cleaned extensively. There was a good amount of Blk dusting throughout.
44-2 had errors yesterday, but today was successful.
Last step before throwing in the towel was reverting the Firmware. There was an update to the PCU Main done a few weeks ago, I reverted back to the previous version thinking maybe the update through something out of whack. No Joy.
I've ordered replacement Reg sensors, and drive units,

Black print / copy is perfect.

50-22 is now NOT printing any patches, removed the TB Cleaning blade to confirm.
attached are samples MX-7500 Samples.pdf

[mojorolla]

I have seen something similar on a 2610, your example looks very similar. In my case, it turned out to be the main drive motor. The error ENC_TIMEOUT_K, indicates an error with the K encoder sensor, which also happens to be in the main drive motor.
In a Sharp machine, the colors use black to align. If black is off, the color will NEVER line up.

[Madnhain]

Right, color references black, and the black print/copy is beautiful... it just won't put the test patch on the TB. Friggin weird.
This is a 4-hour drive to go work on this thing, so I'm packing a bag and heading out first thing tomorrow morning. I'm taking with me a whole mess of parts. (Including the main drive unit).

Thank you for your input sir!

[Madnhain]

I have seen something similar on a 2610, your example looks very similar. In my case, it turned out to be the main drive motor. The error ENC_TIMEOUT_K, indicates an error with the K encoder sensor, which also happens to be in the main drive motor.

You sir, are a gentlemen and a scholar.
First thing I did was replace the Blk Main Drive Assy. 50-22 took a bit of time, but succeeded first try.

Thank you for your input!

[mojorolla]

You sir, are a gentlemen and a scholar.
First thing I did was replace the Blk Main Drive Assy. 50-22 took a bit of time, but succeeded first try.

Thank you for your input!

Thank you Sir.
Glad I could help.