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rowhard
02/21/2009, 06:04 PM
Okay, finally got my beloved VX back friday night from the body shop. It's good, but, will have to take it back for them to re-shoot the hood. But I have a problem. They removed the tail lights and the rear spoiler (3rd brake light) Now, everytime I step on the brakes, I hear a sizzle sound thru the speakers. CD is fine. Ground point maybe??:confused:

etlsport
02/21/2009, 09:26 PM
ground issues are the most common with audio related noises.. but i dunno, at first i was thinking probably grounded the tail lights behind those panels close to the speakers... but then realized that the speakers ground at the head unit.. so i dunno why that would do it.. sorry :_confused

Hotsauce
02/22/2009, 04:06 AM
Is the problem the same with engine on and off?

John C.

Y33TREKker
02/22/2009, 06:46 AM
If everything was put back as it was (wiring/ground points, etc.) I'd maybe start looking at where some of the ground wires are screwed into the frame to check for overspray. If paint got on those areas (and into the threads), it could be preventing as good a ground for the system as there was before.

When you take it back for the hood respray, ask the guys who worked on it which ground wires in particular they remember having to take off and put back on during tear-down and reassembly for places to start looking.

Riff Raff
02/22/2009, 08:22 AM
ROWHARD--- Give fellow Vehicross.Info member "PBKID" a shout, as he is a professional car audio installer at Best Buy. Perhaps he might see this thread and chime in.

P.S.--- Glad to hear your garage-tent wounded VX is nearly repaired from this past Winter's storm damage. I hope their bodywork/paint meets your satisfaction. Aim High!!!

rowhard
02/22/2009, 08:41 AM
Is the problem the same with engine on and off?

John C.

Yes, I just went and checked and it is the same

rowhard
02/22/2009, 08:45 AM
If everything was put back as it was (wiring/ground points, etc.) I'd maybe start looking at where some of the ground wires are screwed into the frame to check for overspray. If paint got on those areas (and into the threads), it could be preventing as good a ground for the system as there was before.

When you take it back for the hood respray, ask the guys who worked on it which ground wires in particular they remember having to take off and put back on during tear-down and reassembly for places to start looking.

Thats just it, what ground wire would they have had to break the connection on. Just remove the taillight housing and headlight housings and bag the rear bulbs. I had removed the amp, sub and face plate before taking it in. Is there a ground in the antenna?

Y33TREKker
02/22/2009, 09:36 AM
Thats just it, what ground wire would they have had to break the connection on. Just remove the taillight housing and headlight housings and bag the rear bulbs. I had removed the amp, sub and face plate before taking it in. Is there a ground in the antenna?
If that's all that was necessary when dealing with the stock wiring harnesses for lights, etc, what about the wiring for the amp and sub you removed? Was the wiring for it also bagged to prevent it from getting hit with overspray? If not, and your amps' power and speaker connectors aren't making as good a connection as they were before, the problem could be there. (And that bring's up another possibility. Where/how is your amp grounded?)

The antenna is shielded to ground to prevent radio interference, but it's not neccesarily a ground in the same sense as a system power ground. I realize it's not the easiest thing to do, but one way to eliminate the antenna wire as the source of the problem without having to start taking interior panels off in the cargo area would be to disconnect the antenna from the back of the head unit and just play a cd (or whatever) to see if the problem goes away. I really doubt that your antenna is the problem though.

etlsport
02/22/2009, 10:07 AM
our antenna is powered iirc.. maybe they grounded it improperly? does it happen on all modes (CD, AM, FM, Aux, etc)

rowhard
02/22/2009, 10:15 AM
our antenna is powered iirc.. maybe they grounded it improperly? does it happen on all modes (CD, AM, FM, Aux, etc)

CD is fine, only checked FM which sizzles and of course that is using a empty freq for the XM Roady XT receiver. AM, never use, but just tuned in, and no sizzle with brakes, but engine whine is real bad.

Y33TREKker
02/22/2009, 11:53 AM
If it was necessary for the shop to remove the interior panels in the cargo area (which it sounds like it was if the antenna was disconnected at some point), it's possible that the connector for the noise suppression filter didn't get reconnected when they were putting things back together.

In the ground distribution section of the electrical troubleshooting manual, a white connector (# R-22) for a noise suppression filter is shown as being located at the "center of rear roof panel, behind trim panel".

rowhard
02/22/2009, 12:17 PM
If it was necessary for the shop to remove the interior panels in the cargo area (which it sounds like it was if the antenna was disconnected at some point), it's possible that the connector for the noise suppression filter didn't get reconnected when they were putting things back together.

In the ground distribution section of the electrical troubleshooting manual, a white connector (# R-22) for a noise suppression filter is shown as being located at the "center of rear roof panel, behind trim panel".

think you might of just hit the nail on the head. page 201-11, plate 72 in the manual shows it. Thanks again

pbkid
02/22/2009, 09:15 PM
sorry, i havent been on all weekend (i got a condo in winter park and went boarding all weekend)...

looks like you guys have narrowed it down very well...

one thing we always do to find sources of electrical problems with audio is slowly 'debuild' your system until you are back to the most basic possible (it can be a pain but it targets the problem exactly)....
it sounds like an antenna ground to me...our ant. is not powered, however, all ant. should have some source of ground... and depending on what they took apart..

my guess is that they disconnected the ground, then sprayed the car, then reconnected and its no longer making a good connection...if you can find where the ground is...you can either sand underneath of it or you can use a 'star washer' that cuts into the paint down to get a good ground...

try to find your ground and see if that helps...