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I have an orion that has been working fine and although it boots and the screen looks right, the control knob has stopped working. It won't respond to either button presses or rotations. I did recheck the cables between the controller and the rambo to make sure that they hadn't gotten loose. Any suggestions on next steps would be appreciated.
Thanks

It may have simply failed. The only thing I could suggest beyond replacing the LCD would be to reseat the cables(disconnect and reconnect them) and see if that helps.

g.

Rotary encoders are cheap and rather ubiquitous. Get one from eBay and try it out.

I determined that the problem is not in the switch or front panel by swapping the front panel with a second, working ORION. Once I put the working panel onto the front of the printer that was not working, I got the same behavior - no button press or turns recognized. Front panel from non-working machine is now working properly on the other printer.

I also erased and reloaded the firmware following steps from here: https://seemecnc.dozuki.com/Guide/RAMBo ... irmware/50
I am noting that on boot-up, the LCD displays the firmware date and number 0.92.2, but does not switch to the temperatures screen.

Am I down to a defective rambo? Other suggestions?
Thanks

Also, maybe related and maybe not, but the yellow LED on the Rambo is cycling where it flashes twice and then the LCD kind of blinks but doesn't change. Then the yellow LED flashes twice....

You might have a short in the I2C wiring to the hot end. Try unplugging the connector from the hot end PCB and power up the Orion. Does the LCD function properly? It may also be that the connector isn't fully seated.

g.

Thanks geneb!!!
I unplugged the cable to the hot end and re-seated it, and the problem went away! Everything, including the knob is now working.

\o/

g.