Welcome to the SeeMeCNC Community

EDIT: It's a Rostock MAX V2.

It is very strange, because the only thing that have been flawless perfection from day one was the Bed Heat. But now it suddenly stopped working. It wont heat up. Stops around the standard heat 23-24 C. The "Led light" is also out. I begining to suspect if something is fried, but nothing indicates that. The wires is also still attached, and they have no damage as far as I can see.

(might be relevant, but most likely no)
I had some minor issue with printing from the SD card, so I clicked around on the printer menu and accidently pressed "Load from EEPROM". I don't know if that made some kind of errors. Like I stated it was totally fine the last time I printed. Have been prinitng for 3 days in total time, and around 500M of filaments.

If anyone know anything how to fix it and how to proceed, help would very much be appriciated. Need the printer to work as I have some important printing jobs waiting for me within the next week.

I'd pull the 15A automotive fuse from the corner of the board and check its continuity with a multimeter.

Firstly, if you can watch the RAMBo before turning on the bed and then turn it on, you should see a bright red heater LED come on. If not, you likely have a blown fuse. Or just check the fuse as IMBoring25 suggests.

I was searching this forum for this exact issue. My bed suddenly stopped working. 15amp fuse has continuity, and power supply is providing power. red LED6 is NOT powering on.

Any additional trouble shooting steps?

Was this ever resolved? Same issue here

Nope, still hoping for suggestions.

aerouta wrote:My bed suddenly stopped working. 15amp fuse has continuity, and power supply is providing power. red LED6 is NOT powering on.

I assume you mean the LED on the Rambo, not on the Onyx? If the LED on the RAMBO does not lit, there is no power send to the bed. The 23-24 C in the OP let's me think there is no heating at all, that's just ambient temp that shows. I am not sure if the heating logic is perhaps controlled by one of the other (tiny!) fuses. I would check those first.

LED6 is the heatbed LED on the Rambo. I have checked the fuses. They have continuity.

Can there be a loose wire at the rambo power input? Seems obvious to check, but maybe missed it?

No loose wire at the Rambo input. Again, the LED light on the Rambo to indicate the heat bed is on does not light. I believe this indicator light should turn on even if there is no power to the heat bed correct?

I am not into schematics, so I really can't say for sure, but I would think it is logical what you say. When you ask the host to heat, does it show the target temp in the lcd display correctly? If so, I think there is a problem with your rambo. Did you do some rewiring or upload new firmware? In that case I am guessing PIN assignment. If the target temp sticks at 0, your host is not giving out the command.

Still getting the damn DEF on both temps. I know that It's the bed as the temp there suddenly dropped from 60c to 24c (room temp) then print stopped.....AFTER 10.5 HOURS OF A 10.6 HOUR PRINT!!!!! If ANYONE has a solution, I am wide open at this point.

DeltaCon wrote:I am not into schematics, so I really can't say for sure, but I would think it is logical what you say. When you ask the host to heat, does it show the target temp in the lcd display correctly? If so, I think there is a problem with your rambo. Did you do some rewiring or upload new firmware? In that case I am guessing PIN assignment. If the target temp sticks at 0, your host is not giving out the command.

Yes it shows the target temp correctly in the in LCD. Yes, i think it is an issue with the rambo also. This may be a good reason to switch to the Duet Wifi board.