extruder not heating, 12v drops to 0v at extruder

Hi,

I am using a ramps board for a prusa i3 printer, its about 3 years old. The printer has been acting up mid prints with "heating failures". Now it wont heat up at all.

I see 12v on the ports from the board but it drops to zero when attached to the extruder.

The 12vs from the PSU does not drop when the extruder is on.

I have also tried changing the extruder and still see the same problem of going to 0v.

Is this a ramps board problem or could it still be the PSU/extruder.

thanks!

Have you checked for continuity in the wiring? There may be a break.

Do you mean from the board to the extruder? I see the drop at the board port.

I can't help with that it could be time for a new board.

Unless Marlin is switching off the port due to some error condition.

Edited 1 time(s). Last edit at 11/05/2020 02:40PM by aamcle.

It could be the MOSFET, easy to replace. You don't have to get a new board, no worries. You should try checking the MOSFET, I don't know how, maybe another member can explain it to you. Anyway, these FET's are cheap, so worth a try. Don't forget to get an upgrade then. I think you can replace it with a IRLB8743?

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http://www.marinusdebeer.nl/

Thanks, I will give the MOSFET option a try. Is it possible to use an external mosfet board like what I have seen for heat beds?