Hi. I've looked everywhere I could online to find an answer, and haven't yet. I believe my issue to be in the software/configuration, so hoping someone here can help.
Background: I bought a Monoprice Maker Select v2 (aka Wanhao DI3). With only minor tweaking, it printed PLA great out of the box. I started my first ABS print after a month of PLA prints, and it was struggling to reach temp... took the bed a long time to climb to ABS temps... and then there was smoke from the control box. I unplugged everything, let it cool, and found that the heatbed connectors to the Melzi had melted.
Rather than RMAing the whole thing (which would have been a lot quicker, but much less 'fun'), or just replacing the connectors, I started looking at DIY options. Ultimately ending up with RAMPS 1.4. I've done a full replacement of the Melzi. I'm running repetier firmware and host. I even picked up an separate heatbed mosfet (Trigorilla).
From the host, all the controls (x,y,z,extruder and hotend) and sensors (stops and thermistors) work as expected, except for the heatbed. When I turn on the heatbed, the RAMPS led lights up, the power supply buzzes, and the temp on the heatbed doesn't climb. I've confirmed I have 12V going into the 5A input (that powers the onboard heatbed mosfet), but there's only 5V coming out of D8 when the heatbed is turned on in Repetier... shouldn't this be 12V?
I was suspect of my RAMPS board. I tried with a new RAMPS and the results were the same. For good measure I even tried a new Mega, with the same result. ...I even switched out a a new power supply, bupkis.
I have to think this is a configuration issue, but haven't seen a setting in the arduino's configuration.h that looks plausibly related to this situation.
What should I check next?
