Hi folks.

I'm an amatuer; I've installed a few decks, speakers, amps etc over
the years, but still know little when it comes to complicated
electrical and troubleshooting. I have a problem that's got me
stumped.

I have a 17 year old car ('87 Porsche 928) that I installed an Alpine
9811 HU in that is cutting out.

I've been trying to troubleshoot and isolate the problem, but can't
figure it out.

I installed the Alpine 9811 HU about a year ago replacing an old
Alpine tape deck/cd changer combo HU. (I'll note here that the old
unit was using the factory wiring for power, so that's what I did with
the 9811 instead of the mfr recommended direct to battery.) It worked
great for about 6-9 months, then after a non-electrical mechanical
project (timing belt job), it started cutting out.

Since it occured when I did the TB job, I assumed they had to be
related. I checked all the cars' fuses, all checked out. I had the
alternator checked and replaced the battery. Everything on the car
looked in check.

My second inclination was that the amplifier blew a fuse. All
speakers were wired from the amp (Amp was getting line level RCA from
the HU), so I removed the amplifier from the equation and ran the
speakers directly from the HU using the HU speaker outputs. That
didn't affect the problem.

During this process, though, I had to pull the HU and I noticed that
the heat sink on the 9811 was getting hot, then cutting out. And the
tiny fan on the heat sink on the back was never turning on, not sure
if its supposed to (I assume so, otherwise why's it there?).

I thought at this point the deck could be broken, so I thought I'd try
operating the unit outside the car to double-check. So, I took the
unit out, wired the power and ground to a battery jumper unit (like a
battery with built in jumper cables), and hooked one of the speaker
outputs to a subwoofer I had lying around to see what happened. The
unit didn't cut out even with high volume after several minutes. The
heat sink was still very hot and the tiny fan on the heat sink still
never came on. But it worked.

I've read that the 9813 and other alpines with the internal v-drive
amps should be run directly to battery because they draw more power,
but my 9811 doesn't have the v-drive.

Could it be I just need to go directly to battery power?
Maybe the unit's overheated and needs to be repaired?
Maybe I need a better ground than the factory harness is providing?

I appreciate any suggestions.

Perx
Huntington Beach, CA

So I did some more troubleshooting and research...

I connected the HU directly to the car battery and directly to the
speakers. I got power, but no sound. So I started disconnecting
speakers one at a time and discovered one of my speaker lines caused
the loss of sound.

Did some research and I guess this is called a speaker short? What is
a speaker short, why does it cause the loss of power, and what do I do
to fix it?

Regards,

Perx
Huntington Beach, CA

"PerxHardlyWorkin" wrote in message
om...
So I did some more troubleshooting and research...

I connected the HU directly to the car battery and directly to the
speakers. I got power, but no sound. So I started disconnecting
speakers one at a time and discovered one of my speaker lines caused
the loss of sound.

Did some research and I guess this is called a speaker short? What is
a speaker short, why does it cause the loss of power, and what do I do
to fix it?


You basically are connecting the positive and the negative together where
they are not supposed to be. First you should eliminate the speaker itself.
Replace it with one of the known good ones. If the problem persists it is
with the wiring, if it goes away then the problem was in the speaker. If it
is the speaker just buy another and go on. If it is the wiring the easiest
thing would be to replace the whole length of wire, rather than trying to
find a short.

Les

"Les" wrote in message
...

"PerxHardlyWorkin" wrote in message
om...
So I did some more troubleshooting and research...

I connected the HU directly to the car battery and directly to the
speakers. I got power, but no sound. So I started disconnecting
speakers one at a time and discovered one of my speaker lines caused
the loss of sound.

Did some research and I guess this is called a speaker short? What is
a speaker short, why does it cause the loss of power, and what do I do
to fix it?


You basically are connecting the positive and the negative together where
they are not supposed to be. First you should eliminate the speaker
itself.
Replace it with one of the known good ones. If the problem persists it is
with the wiring, if it goes away then the problem was in the speaker. If
it
is the speaker just buy another and go on. If it is the wiring the easiest
thing would be to replace the whole length of wire, rather than trying to
find a short.

Les



Speakers generally do not short unless the lead in wires are laying on the
basket. I would suspect pinched wiring.

Chad

"Chad Wahls" wrote in message
...

"Les" wrote in message
...

"PerxHardlyWorkin" wrote in message
om...
So I did some more troubleshooting and research...

I connected the HU directly to the car battery and directly to the
speakers. I got power, but no sound. So I started disconnecting
speakers one at a time and discovered one of my speaker lines caused
the loss of sound.

Did some research and I guess this is called a speaker short? What is
a speaker short, why does it cause the loss of power, and what do I do
to fix it?


You basically are connecting the positive and the negative together
where
they are not supposed to be. First you should eliminate the speaker
itself.
Replace it with one of the known good ones. If the problem persists it
is
with the wiring, if it goes away then the problem was in the speaker. If
it
is the speaker just buy another and go on. If it is the wiring the
easiest
thing would be to replace the whole length of wire, rather than trying
to
find a short.

Les



Speakers generally do not short unless the lead in wires are laying on the
basket. I would suspect pinched wiring.

Chad

True. But it does happen and it is an easy check. Rather than running all
new wire, or searching for the short, only to find out it was a speaker all
along.

Les

"Les" wrote in message
...

"Chad Wahls" wrote in message
...

"Les" wrote in message
...

"PerxHardlyWorkin" wrote in message
om...
So I did some more troubleshooting and research...

I connected the HU directly to the car battery and directly to the
speakers. I got power, but no sound. So I started disconnecting
speakers one at a time and discovered one of my speaker lines caused
the loss of sound.

Did some research and I guess this is called a speaker short? What
is
a speaker short, why does it cause the loss of power, and what do I
do
to fix it?


You basically are connecting the positive and the negative together
where
they are not supposed to be. First you should eliminate the speaker
itself.
Replace it with one of the known good ones. If the problem persists it
is
with the wiring, if it goes away then the problem was in the speaker.
If
it
is the speaker just buy another and go on. If it is the wiring the
easiest
thing would be to replace the whole length of wire, rather than trying
to
find a short.

Les



Speakers generally do not short unless the lead in wires are laying on
the
basket. I would suspect pinched wiring.

Chad

True. But it does happen and it is an easy check. Rather than running all
new wire, or searching for the short, only to find out it was a speaker
all
along.

Les



Then they could disconnect one leg of the speaker and meter the speaker line
at the head unit between the two legs then each leg to ground. No need to
remove and swap speakers, this helps keep the knuckles a little more in tact


Been doing any live work Les? It's been a hopping summer around here!

Chad

You basically are connecting the positive and the negative together where
they are not supposed to be. First you should eliminate the speaker itself.
Replace it with one of the known good ones. If the problem persists it is
with the wiring, if it goes away then the problem was in the speaker. If it
is the speaker just buy another and go on. If it is the wiring the easiest
thing would be to replace the whole length of wire, rather than trying to
find a short.

Les


I understand Les. Thanks.

I think the length of wire actually runs to a passive crossover and
then to two speakers (tweet, mid). Does this complicate my
troubleshooting of the short? Is it possible for the passive
crossover to go bad or short?

Doug

"Chad Wahls" wrote in message
...
Then they could disconnect one leg of the speaker and meter the speaker
line
at the head unit between the two legs then each leg to ground. No need to
remove and swap speakers, this helps keep the knuckles a little more in
tact


That's true, but I don't feel like I've done any work unless my knuckles are
bleeding

Been doing any live work Les? It's been a hopping summer around here!

I am a house guy here at a local venue, we've got one main 2000 seater with
a that has been staying busy. Then we have 2 smaller multipurpose rooms that
are available for whatever that hold about 300 each. So between those and my
own business I'm starting up on the side I've kept busy.

I'm hoping things stay busy so my business can get going, being a house guy
is great but working for yourself seems so much better. I've always said if
I were going to have to struggle to make it I'd rather struggle on my own
terms.

Les

"Les" wrote in message
...

"Chad Wahls" wrote in message
...


Been doing any live work Les? It's been a hopping summer around here!

I am a house guy here at a local venue, we've got one main 2000 seater
with
a that has been staying busy. Then we have 2 smaller multipurpose rooms
that
are available for whatever that hold about 300 each. So between those and
my
own business I'm starting up on the side I've kept busy.

Cool, I'm off the road now working for the UI School Of Music, not bad, but
I miss the road at times. Still doing some mixing but I get to pick and
choose more than live off it. There is a guy here that owns many clubs,
some of which do live music, there is a group of us who rotated thru the
different venues, it was nice to have some change. Now I do more design and
maintence work for them.

I'm hoping things stay busy so my business can get going, being a house
guy
is great but working for yourself seems so much better. I've always said
if
I were going to have to struggle to make it I'd rather struggle on my own
terms.


Amen Brother!, Any local sound companys you can join up with? Freelance
work is great if you have the chops and are in demand. I always like
change, but I also like the big tour money

Chad

"Chad Wahls" wrote in message ...
"Les" wrote in message
...

"PerxHardlyWorkin" wrote in message
om...
So I did some more troubleshooting and research...

I connected the HU directly to the car battery and directly to the
speakers. I got power, but no sound. So I started disconnecting
speakers one at a time and discovered one of my speaker lines caused
the loss of sound.

Did some research and I guess this is called a speaker short? What is
a speaker short, why does it cause the loss of power, and what do I do
to fix it?


You basically are connecting the positive and the negative together where
they are not supposed to be. First you should eliminate the speaker
itself.
Replace it with one of the known good ones. If the problem persists it is
with the wiring, if it goes away then the problem was in the speaker. If
it
is the speaker just buy another and go on. If it is the wiring the easiest
thing would be to replace the whole length of wire, rather than trying to
find a short.

Les



Speakers generally do not short unless the lead in wires are laying on the
basket. I would suspect pinched wiring.

Chad

Thanks Chad, I'll check the wires.

Regards,

Perx

Thanks folks for all the help. I fixed the problem. It was indeed a
speaker short. At the suggestion of Les/Chad, I pulled off the door
panel to see what was going on with the speakers in the door. Boy did
someone do a **** poor wiring job! On the mid, both speaker leads had
about 3 inches of bare wire hanging into the inside of the door metal.
It was a wonder they ever worked. Patched them up and everything
works great.

Thanks for the help.

Perx (HardlyWorkin)
Huntington Beach

Glad to see you got the problem fixed. Just for clarification I would
consider the problem you encountered to be a wire short and not a speaker
short. A speaker short would be internally in the speaker itself, which as
Chad said you don't see very often.

Enjoy!

Les


"PerxHardlyWorkin" wrote in message
om...
Thanks folks for all the help. I fixed the problem. It was indeed a
speaker short. At the suggestion of Les/Chad, I pulled off the door
panel to see what was going on with the speakers in the door. Boy did
someone do a **** poor wiring job! On the mid, both speaker leads had
about 3 inches of bare wire hanging into the inside of the door metal.
It was a wonder they ever worked. Patched them up and everything
works great.

Thanks for the help.

Perx (HardlyWorkin)
Huntington Beach