Blower motor problem help!

I have a 08 wrangler blower motor keeps turning off but when I put my hand to the vent its hot. So I replaced the blower motor and that wasn't the problem someone suggested it was maybe a relay but I camt seem to find a relay that's for the heat, where would it be located? I was going to order the resistor see if maybe be the problem any help would be apprciated thankss