Need Help with heat bed reading (no replies)

Hi,

When i am connecting my head bed to the ramps 1.4 (i am using ramps1.4 with arduino 2560 with marlin as firmware for prusa i3) and its thermistor to T1 the reading i am getting is 0.0 degree in repiter. Although
hotend thermistor is working fine and the led also lights up when i heat hotend. But there is no activity for heat bed neither in ramps nor heat bed. Please help. I am using Semitec 104GT-2 for both hotend and heat bed. My heat bed is PCB HEAT BED MK2B DUAL POWER.

Thanks