Car audio problem, any ideas would be appreciated

[nafe]

Hey guys, i have a aftermarket sound system in my car. It has been running perfect for 3 years, not a hitch. UNTIL my litlle brother came along and tried to "test" his shitty Powervox Amp fresh of eBay in place of one of my amps. Low and behold he blew a 40Amp fuse and had to go buy me a new one.

While he was at Autobahn getting fuses my dad moved my car to put the boat away, the battery grounded itself because my fuse wire was still hanging out. The car turned off and my 1 guage power wire basically welded itself to a screw that it touched.

Now, my sound system makes a buzzing/whining sound (has severe interference) from the motor. And when i turn off the car the subs make a very loud thump.

I have tried the following.

Different amps
different RCA`s
restarting the headunit,
Running the RCA`s outside of the car
Running the speaker wire outside of the car
new fuses (checked every fuse)
motor off (ignition on)
checked spark plugs for arking
re-ground the amps to bare steel
Checked every channel on both amps.
Checked every speaker wire on all speakers and subs

AND THE NOISE CONTINUES ! !

My dad keeps mentioning the "noise supressor" does anyone know if the VX commodore has a built in noise supressor that can blow if the car shorts out?

does anyone have any more ideas that i could try, any help would be greatly appreciated. The only good thing my car had going for it was the sound system and now its gone

 

[headsmess]

yep, thats the suppressor cap alright

um, theres usually one stuck on the old style points, called a condensor, BUT, there also should be one in the back of your stereo blah blah...

take it to an auto electrician and theyll probably charge you 100 bux to replace a $2 component but they know what to replace and where it actually is...

it will be a little metal cylinder screwed down somewhere near your distributor with a wire dangling from one end... does a vx even have a distributor? or does it have the three seperate coils? v6? straight six? v8? i hate cars(except dattos), and dont care what they have in them really....

why cant you ppl stick to the old kingswoods? have it sorted in ten seconds flat stupid efi and hi tech engine management systems

 

[Dabomb]

whats the integrity of the 1 gauge way from the battery like now?
if it was a dead short from the battery to the chassis, it would of melted some the copper/insulation on the 1 gauge positive cable.
this could increase the resistance of the cable, and can lead to RFI and buzzing. so i would replace that cable.

you can get those noise supressors, ive never used one though.

are you spark plugs resistor type too?

 

[headsmess]

oh, rereading it...you got filter caps? like big fuggin filter caps? the thump from the subs sounds like they might have been cooked...either way, its a capacitor somewhere thats doing it. run it off JUST a car battery and see what happens?

 

[Kingers]

Does it still do it whilst the car is off? How has everything been wired up?

Power cable to the amps direct from the battery with inline fuse?
Whats the go with the headunit, has it been wired up using the old wiring loom from the stock headunit?
RCAs and power cable run on opposite sides of the car and away from transmission tunnel?
Is it just your sub that is amped or do you have speakers that run off an amp?
What type of amps and headunit you got?
You got any caps inline with ya power cables?

 

[Dabomb]

you cant have a inline capacitor....there done in parrallel.

 

[foolsp33d]

why cant you ppl stick to the old kingswoods? have it sorted in ten seconds flat stupid efi and hi tech engine management systems

Here here!!!!

although not so much kingswoods, but pre EFI. Carbs are soo much simpler to work with.

But to keep it on subject.. nup.. no idea.. my stero is full of dust, if I try to play a cd i play, gets an error message, and now if i wnt to change the volume, station etc, i gotta give it a whack, so the lights come on, or press the face down hard, then do my adjustments. but I pressure wash the INSIDE of my car also.. so my care facotr is 0.0000001 % Ahhh.. its a sooony.. lol..(actually a kenwoood but shhhh!)

 

[aaron.blake]

try new power cable and also battery clips... i had this happen and it was the power

 

[Kingers]

you cant have a inline capacitor....there done in parrallel.

you know what i meant

Have you tried using another head unit at all? and if you unplug the rcas does the noise dissapear?

 

[aaron.blake]

yeah could be the RCA ive had that prob too haha

worst one happened to me was driving down the rd and then the sterio
stopped... i was like wtf? then looked in my review mirror and saw smoke
coming up though the back seat and tray and so i pulled over poped the
boot and my amp burst into flames lol

now i got a sick system which is running about 126dB

 

[nafe]

thanks for the quick replys guys, heres a bit more info on the system.

Pioneer H/U (running aftermarket wire harness)
RCA`s on different side to the power cable and not near the tranny
Alpine amp for Subs
Some no -name amp for the speakers
1 guage power cable running from battery -> inline fuse -> amp (split to power both)

The power wire still is fine (removed the bit that welded and moved the fuse holder up) but i havent checked the battery`s ground wire yet and i have a feeling that it might have something to do with it.

I also have a feeling that headsmess is on the right track with a "noise supressor" blown.

And yes the problem remains with the car turned off - only with the key turned half way.

No inline capacitors in my system.

I will try running it off a separate car battery on the weekend see what effect that has on it.

Pisses me off knowing how good this thing can sound and while im inside studying for midyears my bro/dad blow it up and i go to get in my car and theres a buzzing+whining+thump comming from my sound system which 2 years ago scored 143 dB

 

[Kingers]

Why would this suppressor cap be interfering with the SQ of the audio? If the Amps are hooked up to the battery there would be no interference to the amps, The Subs and speakers are hooked up directly from the amps so there should be no interference there. The amps get the signal from the HU so there should be no interference there. And the HU Should be hooked up to the battery so there should be nothing there either. Not saying that it wont be this but im just curious as to why it would be this??


Disconnect the head unit and see if the sub thumps.
Check ya trigger wire. May have also welded to the body.
May have blown the fuse on the back of the head unit and then re melted back in place.
Could be somthing screwy internaly in ya head unit

 

[Dabomb]

the remote wire, 'trigger' if you will, doesnt carry enough current to 'weld' to the chasis.
if HU fuse is blown, HU wont turn on.

it could be the screen on the rca cable isnt earthed properly at either end of the cable....doubt it though.

90% somethings been damaged by over current.

have you plugged in a mp3 player into your amp to test that the HU isn't outputting dirty rca signals?

 

[nafe]

The H/u still powers up and runs - it just makes a horrific buzzing/ whining noise that increases and decreases with the rpm of the car. i had to buy some pioneer removal keys of eBay because i lost mine so i will take the h/u out next week sometime.

no i havent plugged in a mp3 player, how would i plug an mp3 player into my amp? the amp takes RCA`s, mp3 players only have a mini jack output?

god i hope its not the headunit, i seriously cant afford that.

 

[fat80y]

For clicking noises on the audio system, use a power supply choke such . If you have a feedback problem, then this can be caused by a bad earth on the system, or a ground loop, in which case a ground loop isolator. For humming noises particular with engine running, try either a power supply choke, or Noise suppression filter where a seperate amplifier is fitted.
to hook up an MP3 playa all you need is a cable from any electrical/auto shop that goes from a 3.5mm stereo jack to stereo(red/white)RCA's - make sure the volume is down 1st lol...

 

[Kingers]

Ok Well i asked your queston on a car audio forum and they seem pretty sure it could be the pre outs on ya HU

Hers 2 replies from the thread




its the head unit. in pioneer head units there are surface mount components on the pre out circuit which burn out easily. pioneers are pretty well known for these being destroyed by voltage spikes, plugging in and unplugging your rca's too fast, or while the systems powered up. get the head unit repaired or replaced. repair should cost no more than $70-80 so dont get stung.




Yep, most likely the head unit. Easy enough to test... Get a bit of wire, touch one end to the shell/chassis of the head unit and the other end to the outer ring of the RCA plugs (while they're plugged in) and see if the noise goes away. If it does, the ground for the RCA's has blown.

 

[nafe]

Thanks for the info kingers, i will do that test by grounding from the RCA to the h/U and see what happens, if that fixes it i will just leave it there permanently lol

 

[nafe]

hey kingerz, thanks for your info. Thanks to you my car is making noise. I wrapped a wire around all the RCA plugs and grounded them to the cage that the H/U fits in. Plenty of wires, every where.

Anyway, do you think this could be a permanent fix? as long as i dont short out the car again?

 

[Kingers]

depends how dodgy you are, if you wanted you could solder the bit of wire onto the pre outs so they dont come off then ground them like it is now, if it was my H/u then i'd probably get it repaired by someone, but my h/u is worth 1000. you could get it repaired for 80 if you didnt want to solder wires onto the back of it or replace it, its up to you, I dont see anything wrong with using the wires as a permanant fix as long as it's done with care and fixed on securly

 

[nafe]

Yeah the wires that i ground onto the metal at attached very well lol theres no way they are coming off anytime soon. I put electrical tape (also heat resistant) around the rca`s so theres absolutely no chance of anything coming loose.

My head unit was worth 1k when i bought it. . i didnt pay that much thanks to some dodgy chinaman, he sent me an e-mail after i bought all my stuff off him saying that if customs opens the package i will get taxed over $4000 for all the electrical equipment, good thing no-one opened it.