Dash lights and ILLUM fuse

[TXredfish]

The ILLUM 10 Amp fuse that is located on the internal fuse block is blowing. It does not always blow right away. It is a 10 amp fuse labled in the WH manual as ILLUM protecting the Instrument Panel Cluster, Audio Alarm, Body Builder Feed. Recently I was on a 200 mile round trip. The fuse did not blow until after travelling 150+ miles and my back lights worked until this time. When it goes out I lose the instrument back lights and the yellow IP cluster dims a little. With the fuse out, I have checked other things like brake lights, turn signals and head lights. The only thing not working is the IP Backlight adjustment thumb wheel, and of course the reason for this is that the IP backlights go out when the fuse goes out.

I have had a dealer work on this problem twice and I have called both Newmar and Workhorse. They have not helped. They cannot tell me what is wired to that fuse. The dealer did replace the back light thumb wheel adjustment, but that only helped for a while. I think that was only a guess. I have tried looking behind the dash with lights out in order to see any arching or wires shorting and have not been able to locate anything.

I have thought about changing from a 10A fuse to a 15A thinking that maybe 10A fuse was just too small.

I have also thought about maybe the wiring on the towing light plug on my tow car might cause this problem. Only because one time I had a loose wire that shorted and blew a brake light fuse that controlled my cruise control and brake lights.

Does anyone have any ideas what else I could check and what may be wired to this ILLUM fuse.

My motorhome is a 2004 Newmar Scottsdale on a W22 chassis.

Thanks for your help...............

[TXredfish]

The ILLUM 10 Amp fuse that is located on the internal fuse block is blowing. It does not always blow right away. It is a 10 amp fuse labled in the WH manual as ILLUM protecting the Instrument Panel Cluster, Audio Alarm, Body Builder Feed. Recently I was on a 200 mile round trip. The fuse did not blow until after travelling 150+ miles and my back lights worked until this time. When it goes out I lose the instrument back lights and the yellow IP cluster dims a little. With the fuse out, I have checked other things like brake lights, turn signals and head lights. The only thing not working is the IP Backlight adjustment thumb wheel, and of course the reason for this is that the IP backlights go out when the fuse goes out.

I have had a dealer work on this problem twice and I have called both Newmar and Workhorse. They have not helped. They cannot tell me what is wired to that fuse. The dealer did replace the back light thumb wheel adjustment, but that only helped for a while. I think that was only a guess. I have tried looking behind the dash with lights out in order to see any arching or wires shorting and have not been able to locate anything.

I have thought about changing from a 10A fuse to a 15A thinking that maybe 10A fuse was just too small.

I have also thought about maybe the wiring on the towing light plug on my tow car might cause this problem. Only because one time I had a loose wire that shorted and blew a brake light fuse that controlled my cruise control and brake lights.

Does anyone have any ideas what else I could check and what may be wired to this ILLUM fuse.

My motorhome is a 2004 Newmar Scottsdale on a W22 chassis.

Thanks for your help...............