Couple months ago middle of night horn started honking like pushing the key fob, took batteries out of key fobs , now intermittently batteries on truck drained over night will not start next morning , could it be a bad GEM

 

maybe just a short somewhere. squirrel or something chewing wire insulation. check horn related wiring first

 

What kind of truck? What motor ? More info

 

Is the horn integrated with the air bag? If the airbag light is on, you probably have a shorter clock spring. Not saying this is what's causing your drain issue but it might be your starting point for additional diag.

-- Dave