Servo pins??

Are the servo pins on the ramps board disabled? I’m not getting anything from them. Following this how-to, sorta.
Basically I just need a signal wire to fire a relay. Using this relay board,
I tried using the heater fan wire like I did with the iot relay, but it runs them backwards, when the fan is on, the relay opens, when the fan is off, it closes. Really don’t want to have the relays powered all the time, only when needed.

You are using the relay from the PDF? It has a Normally open side and a Normally closed side. Leave the middle wire and move the other wire to the other open pin. That should work.

Heh, let the magic smoke out before you replied… Computer sees the mega alone, but if the ramps board is installed, nothing…

Oh no, I think it would be the Vreg on the mega. Dammit that sucks.

The problem with how I had it before it blew up is it wouldn’t energize the coils unless the heater fan was off. The way I was trying was have the 5v input from the ramps hooked up. Then I was using the neg lead from the fan for the signal wire. I’m probably doing this wrong, but couldn’t find a different signal pin to use. That’s why I was asking about the servo pins.

Oh, Dang.

Any specific component on there blown maybe, pop a trace on the bottom? I have a bunch of spares.

Not that I could see. I’m passing by Microcenter this week for work, so I’ll grab a replacement and play with the dead one later. See if I can track down the blown component. I did smell the magic smoke, just can’t see anything blown.