TAZ 4.1 Motors Not Working

Hi, I recently took over for a co-worker who left last year and he was on this forum asking for help to fix the shop’s printer. I’ve run my own tests, but this is what he posted as being how the problem started.

"I have the taz 4.1 at work. We got her fired up and printing last week. She had been sitting in the corner unused for the last year. We did a few of the sample prints and once i learned a bit more about temps and surfaces we had a successful voronoi tower printed. Next day if started the printer and did the preheat, Ran the extruder to clean it a bit and make sure i have a good filament line coming out. I attempted to print the venus de milo sample (SD CARD) and her base started to curve eventually becoming unstable at around the halfway point. She rocked herself out of position and when i discovered this it was a half statue with a glob of melted plastic on top about the size of a quarter. I stopped the print and cleared the mess. After resetting the printer with the reset switch. I started it back up, preheated the unit. But when i sent the unit to “home” Nothing moved. So i attempted to manually via control interface the machine. I chose 1mm for every axis, the extruder one at a time. Nothing is moving. Nothing is functioning. I can physically move the components in the XYZ directions so the unit isnt jammed, and my switches function i checked with a multimeter and manually activated them in checking for “open/closed” indication. What can i do to fix this or troubleshoot further. "

I read elsewhere for connections I need to check, so here is a rundown of what I’ve done so far:

  1. I checked the small fuses and they are just fine. I even swapped them with new fuses from the new Rambo board I ordered and there’s no problem there.
  2. The main fuse is fine as well. Same deal with swapping it from the other board.
  3. I replaced the whole board. The new board seems to work fine, but there’s a new issue with the new board where the LCD screen is blank. It’s on, but it’s just a blank blue screen. I think I may have bought a bad board from the official site, or it was damaged in transit…somehow. Either way I can’t print anything so I don’t even know if replacing it fixes the problem. I’ve checked connections and reassembled it from the OHAI three times with the same LCD problem.
  4. I checked the power connector. 24VDC from the two live pins.
  5. Firmware is up to date as well.

Any assistance helps. I’m at a total loss. I don’t own a TAZ myself, but I do own a Prusa I3 MK3 at home.

I know you said the firmware was up to date but I have to ask, did you update the firmware since installing the new RAMBo? The RAMBo won’t come preloaded and almost every time I see someone have a hard time with the LCD screen not fully coming on after installing a new RAMBo it is because the the firmware hasn’t been flashed or the wiring got flipped around.