Front clearance lights do not work!

I have been a member of this site for a few years but never posted before, so bear with me.
I have a 2003 Coachmen class C Freedom on a Chevy chassis. It all began when I noticed two of my front clearance light lens were cracked, apparently a limb hit them on one of our last trips. I tried to turn the lights on to see if they were affected or just cracked....no worky! I bought two new lights, with bulbs and replaced them. Still they didn't come on. So now i"m thinking fuse...but wait that can't be it because the back lights all work, up front the parking lights come on but not the top lights. I checked all fuses anyway. All wire connections I can see or feel seem good. All I can think of is this....is it at all possible that the lights are wired such that when one goes out they all go out. The two bulbs I replaced were not bad. My only recourse is to remove the three lights to check the bulbs. The lens has a clear inspection spot in the lens but I can't see the bulb filament well enough to tell if it is blown. All comments are welcome!