Â* So 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 !

--
Snag
Yes , I'm old
and crochety - and armed .
Get outta my woods !

On Tue, 24 Sep 2019 07:56:02 -0500, Terry Coombs
wrote:


* So 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 !



.... 1986 ! ? . . . could be a problem with the 8-track .. :-)

Any signs of mice ?

Any " un-related " non-electrical work done on the truck
that might have disturbed fragile 1986 wiring ?
eg : tilt-steering adjustments by a new driver ?
John T.

On 09/24/2019 06:56 AM, Terry Coombs wrote:
'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 !

What else is on that fuse? Does it still blow if a radio isn't connected?

http://forum.73-87chevytrucks.com/sm...?topic=11766.0

'radio' isn't jumping out at me but your eyes might be better.

On Tuesday, September 24, 2019 at 10:02:52 AM UTC-4, rbowman wrote:
On 09/24/2019 06:56 AM, Terry Coombs wrote:
'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 !

What else is on that fuse? Does it still blow if a radio isn't connected?

http://forum.73-87chevytrucks.com/sm...?topic=11766.0

'radio' isn't jumping out at me but your eyes might be better.

Sounds like an intermittent short in the supply wire. Try driving with the radio off and see if the fuse still blows. If so, you can try to follow the wire back to find it, or else maybe run a new wire with online fuse from somewhere. You can sell the radio on eBay.

On 9/24/2019 8:22 AM, wrote:
On Tue, 24 Sep 2019 07:56:02 -0500, Terry Coombs
wrote:

Â* So 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 !


... 1986 ! ? . . . could be a problem with the 8-track .. :-)

Any signs of mice ?

Any " un-related " non-electrical work done on the truck
that might have disturbed fragile 1986 wiring ?
eg : tilt-steering adjustments by a new driver ?
John T.

Â* No other work has been done that would have caused this . No sign of
mice or any other damage to the wiring . Much as I hate to , it might
come down to opening up the harness to trace this out . Gotta give it
some more thought before I go there .

--
Snag
Yes , I'm old
and crochety - and armed .
Get outta my woods !

On 9/24/2019 9:02 AM, rbowman wrote:
On 09/24/2019 06:56 AM, Terry Coombs wrote:
'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 !

What else is on that fuse? Does it still blow if a radio isn't connected?

http://forum.73-87chevytrucks.com/sm...?topic=11766.0

'radio' isn't jumping out at me but your eyes might be better.

Â* Thanks for the link , it should help . I'll have to print some of
those out and see if I can tape them together ... it's not clear on
those diagrams , but as far as I can tell the radio is the only thing on
that circuit . At least it's the only thing that dies .

--
Snag
Yes , I'm old
and crochety - and armed .
Get outta my woods !

In article , says...

* So 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 !




Can you just run a wire from another place through a fuse to the radio
? That would tell if it is the radio or the wiring. I am sure you
checked, but is the fuse the correct value and not just one that someone
in the past has changed for the wrong value.

On 9/24/2019 9:39 AM, Ralph Mowery wrote:
In article , says...
* So 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 !



Can you just run a wire from another place through a fuse to the radio
? That would tell if it is the radio or the wiring. I am sure you
checked, but is the fuse the correct value and not just one that someone
in the past has changed for the wrong value.


* I have considered feeding it from another switched power lead . The
15 amp fuse that was blown when I got the truck back was replaced with
the same value - my last one , so when it blew I used a 20 which also
blew . I'm pretty sure the smaller fuse in the new Pioneer unit would
blow before the supply fuse if the problem was with the radio . And
since it did the same with the previous radio , I'm sure the problem is
in the truck wiring .

--
Snag
Yes , I'm old
and crochety - and armed .
Get outta my woods !

Terry Coombs wrote:

Â* So 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 out of curiosity, I would put an amp meter across the fuse
terminals with the radio off and the fuse removed to see if there is a
draw of current for the circuit. I had an instance were there was a
drain on my battery with everything off, and it was a power relay for
the horn circuit. Not enough to blow the horn, but enough to discharge
the battery over time.

On Tue, 24 Sep 2019 07:56:02 -0500, Terry Coombs
wrote:


* So 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 !
Try checking the cig lighter circuit - on a lot of Chevy trucks the
radio and lighter share the same fuse

On 9/24/2019 9:32 PM, Clare Snyder wrote:
On Tue, 24 Sep 2019 07:56:02 -0500, Terry Coombs
wrote:

Â* So 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 !
Try checking the cig lighter circuit - on a lot of Chevy trucks the
radio and lighter share the same fuse

Â* Not on this one , the lighter is always hot . That's where I pulled
the memory power for the radio from . A Chevy truck forum post I found
indicates that on this model the radio is the only thing on that fuse .
On Friday I'll be pulling the fuse block to check for damaged wires
behind it - if I don't find any problems there I'll probably be running
a new power lead from the fuse block to the radio .

--
Snag
Yes , I'm old
and crochety - and armed .
Get outta my woods !