New Noise

Phoenixcolt · Post by **Phoenixcolt** » Wed Dec 12, 2007 4:00 pm

Sup guys, hope everyone is well. I haven't been around much because I been busy trying to better my life a bit but I def miss the forum. Started a new job after Tgiving with The Hartford Insurance so that's some good stuff and am starting to think about systems again since I will have a little money to play with soon enough. Nothing crazy elaborate but a start.

I am planning to raise my hatch floor in the Golf and make a subfloor to house my comp crossovers, an RSd500.4, and a voltmeter complimented by a couple hidden blue neons for that special glow : )...I have so much stuff left over from the Colt for accents I figured I would use a little in the dub. A subfloor type setup will allow me to secure my stuff pretty tight and I think it would look pretty sweet to have that stuff inset with a little view window or something under the primary hatch floor cover to open up when I am hangin out and stuff.

Anyway...Before I can even start that project, I have a problem.

I am getting tons of steady electrical noise when the car is not started and bad alternator noise when the car is started. I didn't have this problem before and I can't figure out what has changed since my last setup in the vw. I know this topic has been revisitied over and over but what the hey, that's what we're here for right? I have tried 2 amps on the same wiring and got the same result.

I know there was a really great writeup someone posted for amp noise on the forum a while back but I searched and searched and couldn't find it. Do you have any idea what post it was in or where I can find the same writeup?? Mozilla deleted my bookmarks one upgrade and I lost the site. It was very informative, had all types of noise descriptions and how to isolate items to fig out where the noise is originating and all that good stuff.

Hope you can help. Thanks guys.

Phoenixcolt · Post by **Phoenixcolt** » Wed Dec 12, 2007 4:15 pm

Got It, tech tips 101.

Regardless, why do you think I would be getting this noise now if I didn't before using the exact amp and setup?

Changes since my last vw install...added compustar car alarm and remote starter and put RSd coaxes up front until am ready to install comps again.

Attempts to resolve...wiped pos batt terminal down which was very corroded, relocated amp ground, moved amp around, and checked fuse connections for amp after battery.

None of those things helped.

Has anyone ever had noise trouble using a silver or nickel ring terminal off the pos battery terminal? I dunno if that could contribute but I wouldn't doubt it had some effect.

Post by **Bfowler** » Wed Dec 12, 2007 4:22 pm

were any of the wires ripped/broken when they stole the gear from before?

what is the amp mounted on?

does the noise come through everything? just front? just sub?

Phoenixcolt · Post by **Phoenixcolt** » Wed Dec 12, 2007 4:32 pm

Haven't hooked sub up yet, only tried hooking up the front speakers but the rcas for the front and rear both put out the same kind of noise and I believe I even hooked up the sub rcas for a brief testing period to the front channels and they also yield the noise. It seems the sound is coming through all 3 pairs of rcas but it never did before.

I think the speaker wires were all ripped at the ends, they ripped my rmd wire, and they may have pulled hard at the rcas but none of them appeared damaged. I unscrewed the rca ends to see if any connections looked f-ed up but they seemed fine, the rcas I use are the PG green ones I got through you.

Amp was mounted on the hatch floor as was.

I wonder if there is some internal rca damage that I cannot see.

Post by **Bfowler** » Wed Dec 12, 2007 4:35 pm

try mounting the amp on a board...

did they take the deck? how is it grounded?

Phoenixcolt · Post by **Phoenixcolt** » Wed Dec 12, 2007 4:39 pm

No I don't even think they touched the deck because I luckily had the faceplate out.

The amp is grounded to sheet metal that has the paint scraped away. It is the same ground that worked flawlessly before.

Would a board serve the same purpose as me picking the amp up while it was operating to see if the noise went away?

Post by **stipud** » Wed Dec 12, 2007 5:28 pm

Phoenixcolt wrote:Would a board serve the same purpose as me picking the amp up while it was operating to see if the noise went away?

Yep. Fuzzy had the same issues with the M series amps in his car. My Ti amp doesn't seem to do this, but I do have it mounted on rubber standoffs...

Phoenixcolt · Post by **Phoenixcolt** » Wed Dec 12, 2007 5:30 pm

stipud wrote:
Phoenixcolt wrote:Would a board serve the same purpose as me picking the amp up while it was operating to see if the noise went away?
Yep. Fuzzy had the same issues with the M series amps in his car. My Ti amp doesn't seem to do this, but I do have it mounted on rubber standoffs...

So if I just pick the amp up and the noise doesn't stop, I should try something else right? Cuz I have tried picking it up a couple times to see if the noise would stop but it sadly did not.

Post by **fuzzysnuggleduck** » Wed Dec 12, 2007 6:05 pm

My noise problem is related to the amp chassis touching my vehicle chassis through the mounting screws. Once I dealt with that issue, my noise almost totally went away.

Since that's not your problem, I don't really have anything to add.

Phoenixcolt · Post by **Phoenixcolt** » Thu Dec 20, 2007 3:08 pm

Do you guys think that my remote starter that was added could have something to do with my new noise issue?

It is the only thing that makes any sense to me but I may have silly ideas.

Depending on where the alarm/starter ground was mounted under the dash, is it possible that the brain could be picking up the noise I am hearing through the tach wire that is run for the starter and that the brain ground could be sending spent brain power into the chassis that my amp ground is picking up? Is that what a ground loop is?

My battery rests at 12.2 and charges at 14.5 which seems ok, I cleaned off the + post of corrosion, the rcas are fine, and the power and ground have not been changed since I last ran my amp except for a redo on the power ring terminal on the battery.

Post by **Bfowler** » Thu Dec 20, 2007 3:10 pm

ooooh! if he grounded your alarm with the head unit...it could absolutely add noise.

Phoenixcolt · Post by **Phoenixcolt** » Thu Dec 20, 2007 3:14 pm

Ah ha!!!!!

I will check that very soon...altho my headunit is grounded through a wiring harness but he may have tapped into the ground the wiring harness leads to.

So my headunit is prob the culprit which would make sense because the sound stops when I pull the rcas out...so I will probably have to ground my headunit somewhere else...rather than dig under the dash in search for the ground connection unless it's very easy access.

I am excited because I want this noise to go away. I haven't had front speakers in months : (

shaheen · Post by **shaheen** » Fri Dec 21, 2007 3:24 am

What headunit is it, something to try is to ground the outer sheild of the RCA's to the headunit ,

have u tried a new RCA over the top , meaning a complete new cable and runn it over the seats to the amp.

U have an uprated alt as well , could be the alt which has something faulty.

I would try the RCa's first, they may not appear faulty , but could be.

Post by **Bfowler** » Fri Dec 21, 2007 8:42 am

you could use this time to ground the head unit to the same place your amp(s) are also...

Phoenixcolt · Post by **Phoenixcolt** » Fri Dec 21, 2007 2:33 pm

Bfowler wrote:you could use this time to ground the head unit to the same place your amp(s) are also...

Just to have a common ground going on u mean?

Post by **Bfowler** » Fri Dec 21, 2007 4:06 pm

yep. just for the audio compents though, none of the normal car systems/alarm.

Post by **VW337** » Fri Dec 21, 2007 4:57 pm

Do you have neon installed?

Noise with the car off and it get worse with the car on?

when the car is off but audio on, knowing vw's as I do, does your accessory turn on/off when you remove the key or put it in or does it have to be turned? what year car?

is noise present with the sytem on and RCA's disconnected at the HU but plugged into the amp, and/or vice versa?

is the amp resting on the floor or mounted to the side, if the side DR or PASS? Where are the passive XO's for your speakers mounted?

Phoenixcolt · Post by **Phoenixcolt** » Sun Dec 23, 2007 3:25 pm

VW337 wrote:Do you have neon installed?

Noise with the car off and it get worse with the car on?

when the car is off but audio on, knowing vw's as I do, does your accessory turn on/off when you remove the key or put it in or does it have to be turned? what year car?

is noise present with the sytem on and RCA's disconnected at the HU but plugged into the amp, and/or vice versa?

is the amp resting on the floor or mounted to the side, if the side DR or PASS? Where are the passive XO's for your speakers mounted?

No neons.

Yes, with car off, a steady and quieter hum, with car on, loud alternator noise.

98 Golf. And I believe I have to turn the key one click to acc for things to work.

The noise goes away with the rcas pulled out of the amp, I will check tomorrow if I can still hear the noise with rcas out on the HU side.

Either amp I tried was on the carpet, no screws or anything for mounting but the noise doesn't stop if I pick the amp up or move it around. I have not reinstalled my passives yet, I just have coaxes mounted right now.

Post by **VW337** » Sun Dec 23, 2007 8:15 pm

noise goes away with RCA's out of the amp, that eliminates a few things.

Run an 18AWG cable from the HU chassis to the amp ground. What happens to the noise, does it go away, get quieter, or get worse?

What is the result with the RCA's connected to the amp and disconnected from the HU this will be the telling factor. While you have the RCA's off at the HU short the ends pin to ring on all RCA's. If the noise goes away with them disconnected and comes back with them shorted you have a bad RCA unshort them one at a time until the noise goes away, when it goes away you know which one needs replacement. If the noise stays gone with them shorted, you then need to plug one at a time back into the HU to see if you have a bad HU output, if you get noise on the first one then unplug it and try the next. Post results in detail if you can.

At this point your possible issues are shorted to chassis RCA, bad ground at HU or bad HU.

I wouldn't look at the alarm as an issue as it is inactive when the radio is on, unless the FM tranciever is mounted to the top of the HU it should not be a factor.

Phoenixcolt · Post by **Phoenixcolt** » Mon Dec 24, 2007 1:31 pm

So I pulled my HU out and I am not sure if it happened as I pulled it out or if it was already this way, but 2 of the sets of RCA wires that come out of the HU were pulled out and bare wire was exposed. I wish Clarion used beefier wire for that...and I wish I knew if I did that just today or if it was already like that so I could fig out if that was what was causing the noise.

Shorted RCAs could have been the culprit after all. I am now going to install my Pioneer DVD unit from the colt between today and tomorrow and hopefully I will not have any more issues but I will keep the forum posted.

I have been told that the older Pioneer DVD unit parking brake wire can be grounded and will bypass the safety, hope thats true...

Post by **VW337** » Mon Dec 24, 2007 1:57 pm

Phoenixcolt wrote:I have been told that the older Pioneer DVD unit parking brake wire can be grounded and will bypass the safety, hope thats true...

Depending on the model yes. some of the newer units have a gyro system.

Phoenixcolt · Post by **Phoenixcolt** » Tue Dec 25, 2007 2:38 pm

K I was able to do a test run with the pioneer. No engine noise...had to be my clarions pulled out wires. Sorry I didn't see that initially so we didn't have to speculate : ( . Thanks for all of the responses though.

I do need to put a switch in for the parking brake safety, I tried grounding the parking brake wire with all of the other grounds but it told me I couldn't view video while driving.

If I add a switch, is it just green wire to load side and a ground wire to line side? I have a rocker switch with 2 prongs on the bottom. Not sure if there are different switches that are better.

Post by **VW337** » Wed Dec 26, 2007 10:29 am

you got it.

Again the model makes a difference and it may have the Gyro. If it is a N1?D1 or older you are okay if it is newer then it has the gyro which takes advanced hacking at the board level.

Phoenixcolt · Post by **Phoenixcolt** » Wed Dec 26, 2007 11:43 am

VW337 wrote:you got it.

Again the model makes a difference and it may have the Gyro. If it is a N1?D1 or older you are okay if it is newer then it has the gyro which takes advanced hacking at the board level.

It actually isn't either of those, it is an AVH-P7600DVD, no navi, but you can purchase an addition for it that will give you your direction of travel and engine info and such so perhaps it has a gyro within.

I had a switch on it in the Colt and it was all good, and it is easy enough to add again for the vw so it should be cool.

Post by **VW337** » Wed Dec 26, 2007 12:59 pm

the 7600 is an older model as mentioned in fact I think it was the year prior to the N1/D1 so you should be good.

Yes it does in fact error if it is to ground constantly, you'll need to ground/unground it every so often for it to reset, this is an early safety measure.