"Leon Fisk" wrote in message
...
On Tue, 24 Sep 2019 07:58:47 -0500
Terry Coombs wrote:

When I got my truck back from our son , lots of things that he just
couldn't be bothered to fix . One thing is the radio power supply .
He
did tell me that the radio had "died" , turns out the fuse (in the
fuse
block) keeps blowing . I've got the dashboard apart enough to check
the
wiring harness and supply wires , can't find any cuts or anything
that
looks like damaged insulation ... it works just fine sittin' in the
driveway , but within a few miles driving it blows the fuse . I
figured
it was the radio/CD player unit so I got a new one , does the same
thing
. I'm really puzzled by this , from the way the fuse was spattered
it's
got to be a dead short to ground . I think it very unlikely that the
new
radio/CD unit is bad - the old one did work when I replaced the fuse
,
for a few miles same as the new unit . This is an '86 GMC pickup ,
I'm
hoping someone here might be aware of a known problem area that I
might
check ... I gotta have tunes !


Just some random ideas... Does it have a power antenna? (doubtful)

Check the fuse schematic and see if anything else uses the same fuse?

Any kind of work/replacement done than might have pinched a wire
underneath or shot a new screw threw a wire?

Some speaker systems run "hot leads" and do not behave well
if a lead gets grounded...

--
Leon Fisk
Grand Rapids MI

=====================
Good suggestion.

I prioritize my troubleshooting sequence partly by how quick and easy
the tests are with available equipment. How would you check for an
intermittent speaker wire short to ground?