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So I get everything hooked up and power it on and instantly my heatbed started heating, I had it hooked up to pin 2.7. so I shut down the machine and check my config, the only reference to pin 2.7 that i could find was in my heatbed temperature control section. so i rewire things and hook my hotend up to that pin and redid the config to match and the heatbed is fine on 2.5 but the hotend starts heating as soon as i power on the board. anyone have any ideas?

I attached my config file if anyone wants to look at it, i converted it to a txt so the forum would let me upload it.

Sounds like the big mosfet (AOT240L) failed closed and that will automatically turn on when powered up.


https://docs.google.com/spreadsheets/d/ ... edit#gid=0" onclick="window.open(this.href);return false;

is this an easily fixable thing, or should i just not use that connection?

It's like a $2 part with three solder points. Quick and easy to replace, or you can just work around it. Just be careful because the smaller mosfets cant handle the same amperage.

http://www.digikey.com/product-detail/e ... ND/2769834" onclick="window.open(this.href);return false;

It's an easy repair in theory but the board design allows it to absorb a lot of heat so it can be a real bear removing the old FET and getting a good joint on the new one.

WZ9V wrote:It's an easy repair in theory but the board design allows it to absorb a lot of heat so it can be a real bear removing the old FET and getting a good joint on the new one.

board design?, okay. The mosfet has a little heat transfer pad but nothing crazy. If you can solder the wires on the Onyx PCB, you can replace the mosfet.

Worst case? cut the pins with flush cutters and remove each pin separately.