Roof marker lights not working

[Geodev]

Hi I am new to this forum. I have a 2007 four winds class c on ford chasis. My roof top marker lights over the cab went out and I dont know why. I have done research and i still cant find where the fuse is located for these lights. Has anyone else had this problem?

 

[16ACE27]

Has anyone else had this problem?

Yes, many threads here about marker lights being out. Less likely to be a fuse and more likely to be a wiring issue connection or ground connection issue.

 

[Number Three]

What 16ACE said. What I've found in the RV's I've had (which were a popup, a small towed camper and this class c), is that there's a major difference between the ground connections in vehicles and those in all of the RV's I've had.
Having a fiberglass instead of metal shell, ground wires have to go a lot farther to connect to the chassis ground, or a ground buss somewhere. So the issue is just as likely to be the ground, as it is the positive buss, or the fuse.

Get a long wire and connect it to a nearby, known ground, or the negative post of the battery. Touch the other end to one of the ground connections at the lights. If it works, you know you're missing ground.

If no joy when you jump to the ground connection at the light, you'll know the ground buss is probably OK. So remove your jumper wire and connect it to the positive terminal of the battery. Touch the other end to one of the 12V sides of the lights. If you have lights, the positive buss is open somewhere.
Once you know which side is open, you can concentrate your hunt to that side.

 

[ghnl]

IIRC (but often I don't...) in our 2004 Class C on Ford E450 chassis there was a gang of wires sort of stuffed into the front, left corner of the motorhome. It may have been behind a piece of trim. When the front marker lights decided to stop working I eventually found a loose connection in that gang of wires.

 

[Geodev]

What 16ACE said. What I've found in the RV's I've had (which were a popup, a small towed camper and this class c), is that there's a major difference between the ground connections in vehicles and those in all of the RV's I've had.
Having a fiberglass instead of metal shell, ground wires have to go a lot farther to connect to the chassis ground, or a ground buss somewhere. So the issue is just as likely to be the ground, as it is the positive buss, or the fuse.

Get a long wire and connect it to a nearby, known ground, or the negative post of the battery. Touch the other end to one of the ground connections at the lights. If it works, you know you're missing ground.

If no joy when you jump to the ground connection at the light, you'll know the ground buss is probably OK. So remove your jumper wire and connect it to the positive terminal of the battery. Touch the other end to one of the 12V sides of the lights. If you have lights, the positive buss is open somewhere.
Once you know which side is open, you can concentrate your hunt to that side.

Thank you so much! You explained this very well.