'97 Tahoe electrical problem

hi. my '97 Tahoe has been blowing the fuse of the interior lights and courtesy lights. The same fuse also runs the electric mirrors. I have tried to locate
the short, but it is intermittent... in other words, it only happens when you are not looking for it. It may go for a week or two without blowing, or it may not last a day. I have checked the physical condition of wires, switches, lamp fixtures, where I can get to them, but no luck. I have seen where there is a "black box" which controls I guess the delays of the lights, etc... but I have no way of testing it...
has anyone else come accross this problem?
thanks
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
check the cig. lighters. front and rear for a loode element or something like a penny in it.....

courtesy
locate
you
it may

lamp
is a

have
--
Outgoing mail is certified Virus Free.
Checked by AVG anti-virus system (http://www.grisoft.com ).
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Motorsforum.com is a website by car enthusiasts for car enthusiasts. It is not affiliated with any of the car or spare part manufacturers or car dealers discussed here. All logos and trade names are the property of their respective owners.