92 honda prelude, battery turns off after turning ignition, just replaced main relay?

i have a 92 prelude Si, had a problem with the main relay earlier, now i have just bought a main relay and put it in, so when i put the key in i get power to the car, but when i turn the key to start it, the battery just shuts off (no clicking or anything), but if i take the cables off the battery then put them back on the battery will work again but same thing when trying to start it, i have recently moved from florida to north carolina and the car was sitting for a couple months in some pretty cold weather, just wanted to get any suggestions, thank you