i replaced my exterior temp sensor and it does not show it on the dash. reset??? on 2006 Mercedes-Benz S350

is there anything i have to do to reset it or could it be a wiring problem. but heres the good part i put through a touchless car wash and the high pressure of the water turned it on for 3 days and it reading a real high temp but then it stopped working

Asked by for the 2006 Mercedes-Benz S350