I bought a used Prusa i3 that I'm in the process of learning and cleaning up along the way.

Only half the heated bed seems to be getting hot. Looking at the MK2B bed, it looks like there might be two heating elements, which can be connected in series (Pins 2 and 3) if powered by 24V and in parallel (Pins 1 and then 2/3 tied together) if powered by 12V.

Checking the connections, it looks like pin 2 isn't connected, so only 12V is going to 1 and 3 - half the bed!

QUESTION: If I tie in pin 2, I'm doubling the current requirements on the RAMPS 1.4 board. Will I burn it out? My power supply is rated at 12V 20 Amps, so it looks like the power supply is sufficient. But I don't know the specs on the RAMPS 1.4 board D8 connection, and I also don't know the power requirements for the MK2B.

Thanks.