GR3770 stuck in a loop

[DWG]

Was printing fine last night until I removed a drum and inserted a different one into the machine...

The drum started turning as it sometimes does in idle after start up, but was blinking ' - PLEASE WAIT - ' instead. This went on for way longer than I think is normal. I opened the door and lifted the drum handle, and the drum stopped at the next home position and released. I swapped it for a different color drum and the same thing happened. I let it turn for a good 15 minutes before finally I just shut it off. Tried a hard reset on power up, but as soon as I flipped the power switch it started rotating. Turned off and on again, tried to initiate Test Mode (which it went into, as was visible on the LCD) but could not enter and test numbers--because it was STILL spinning.

Came back to it this afternoon. Turned it on and guess what? You guessed it! Still spinning.

Any ideas? Wondering if something is tripping a sensor or what??

[DWG]

Re: GR3770 stuck in a loop

https://youtu.be/CWJOQaYyyN0

here's a look from the back of the machine, please help if you can

[20gaugeO/U]

Re: GR3770 stuck in a loop

What was the last drum that worked in it (black)??? Put it back in and see what happens. Scrap piece of paper between drum and machine connectors causing poor connection?
What else happened? Any work on the machine, lightning strike or power surge?
Are these other drums "new" to you?
TM 97 is an all memory clear if you can run it (next level up from a hard reset)

[DWG]

Re: GR3770 stuck in a loop

20 Gauge, thanks for responding.

The last drum that worked in the machine was black(HD). I've tried putting the exact one back in, but the same thing happens regardless of drum or color. No power surge or lightning lately, I have it on a surge protector strip anyway. This machine has not been worked on since it's been in my possession, save my tinkering. I got it with the drums around 4 months ago, and it had some quirks. Since I got it home, cleaned it and ran a few TMs it's been printing fine, with a few exceptions*.
I can't tell that there is any obstruction between the drum and connectors on the machine, which I assume are the small connection cartridges (one vertical, one horizontal) located on the bottom of the drum, and on the machine below the drum slot at about 5 and 6 o'clock... if there are other spots I should be checking let me know!

As for Test Mode 97:

I've tried test modes, but like I mentioned, it won't let me enter digits at all. When I turn it on in TM it just spins away, with the LCD displaying typical test mode text. Since I can remove the drum without issue, I did and turned the machine off. When I started back up I initiated TM and entered 97. The machine reset and then showed the INSERT PRINT CYLINDER prompt. I did and the incessant spinning began again.

Pretty stumped at this point. Thanks again for your advice!


* - [ it's had some trouble with image registration between drums, and sometimes with paper feed errors. These both happen infrequently, but I have two parts machines I could take from to replace clutch motor or otherwise if that seems to be the problem. Aside from replacing the feed assembly (rollers, stripper pad, etc.) is there anything I should be doing to avoid either of these issues? ]

[jermyth]

Re: GR3770 stuck in a loop

Have you tried holding the reset button while turning on the machine, a holding for 5 - 10 seconds?

[DWG]

Re: GR3770 stuck in a loop

-FIXED-

jermyth, I did try the reset on start (one of the very first things I did) but the drum just went right on spinning.

I am not exactly sure what was malfunctioning, but I started to examine the area where the handle of the drum latches into the machine. Like I mentioned, it would stop idling and let me remove the drum if I lifted the drum handle to the removal position and the green light illuminated. After carefully reinserting the drum a few times I noticed something didn't feel right about the positioning of the handle. I kept repeating the process and finally felt something change and the handle was in what I assume is the correct downright position.

No idea how it fixed itself but I sure am glad to have it back up and running. Still a head scratcher.

Thanks guys