License Plate Lamp Issue

[Mike M]

I have a 1989 Excella with a license plate lamp that works only intermittantly. All the other lights work properly. I checked the lamp with an electrical tester with the ground on one of the tail light grounds and it is not hot. I am not sure if I have to remove the interior walls to trace the wire or if there is a fuse somewhere. Any help would be appreciated. Thanks,

Mike

[Jim & Susan]

Sounds like a bad ground. If there is only one wire in the light socket, then it grounds thru the body of the camper. These types of grounds are notorious for going bad. If you can easily remove the socket, check where it attaches to the aluminum body of the camper and see if there is any white looking power stuff. That is alum. corrosion. Clean that with a Scotch Brite pad and reattach, see if that clears it up.

Also check the tab at the base of the bulb inside the socket and see if its corroded or dirty.

Last, check the wire as far up as you can see it and look for any breaks or "skinned" areas. Anyplace that it may be grounding against the trailer. This doesn't seem likely, tho, because you would think a short would pop the fuse.

Let us know what you find.

Jim

[87MH]

Originally Posted by Mike M

I have a 1989 Excella with a license plate lamp that works only intermittantly....

Mike -

Welcome to the Forums.

I totally agree with Jim's comments on the grounding problems.

I just the other day buttoned up the center rear panel under the window (the "front" panel to the license plate bracket), so I can attest to the wiring.

Pulling the center interior panel is no biggie - about 50 or 60 rivets is all.

On the wiring - both the positive AND the negative (ground) wires had "quick connects" on them...in addition, the ground was routed to the curb side and connected with several other wires (grounds for the curb side running lights) before being connected to the body for grounding.

On the new license plate bracket I installed there was NOT a wire included for grounding - the ground is implemented through the screws which hold the bracket to the body.

You might try replacing the bracket screws (even on my old one - '78 vintage Sovereign - the bracket attach was via sheet metal screws - not stove-bolts and nuts), sometimes the screws become a bit loose and a thin layer of rust developes between the screws and the aluminum.

Be sure to use some sort of vapor barrier on the new screws to prevent water from entering the rear of the trailer at this point - the rear 6" or so of the floor was the only area I found moisture damage when redoing the '78.