So close to getting my first printer going. I have a Rework I3 with Ramps 1.4, E3Dv6 hotend, and MK2B heatbed. In Pronterface I try to heat the hot end up and it won't go above 140C but when I check the hot end with an infrared thermometer it is only around 30C. The light on the Ramps stays on and solid red while heating. When I heat the bed I have similar issues, it won't get very hot and reports quite a bit different than when i take surface temp. The red LED on ramps and blue led on MK2B turn on and as it heats higher they both flicker. I checked the voltage on the bed when they are flickering and it is very sporadic between 8 and 12 volts. Any suggestions for my Marlin or other settings? I assume the pronterface is just reading what I uploaded from Marlin and is not changing settings on top of Marlin?

I have Marlin set for the following:

#define TEMP_SENSOR_0 5
#define TEMP_SENSOR_1 0
#define TEMP_SENSOR_2 0
#define TEMP_SENSOR_BED 1

I think they are right. I tried the PID tuning and get a failure timeout error. Is there a way to ohm out the thermistors to determine I have correct wiring and no shorts? Is there any special settings I need to do in Pronterface? Why would the bed voltage fluctuate when heating?

My power supply is 12v 30A [www.amazon.com]
When the hotend is heating I checked the voltage at the blue terminals where the hotend wires go in and its getting 12.8v.

Is there anything that I should be checking in Pronterface or the Repetier that would screw something up?