so let me start of by saying i am a car audio installer and now i am stumpped at a ground loop issue. first i have to replace my blower motor in my car and that involved removing the complete dash. while it was off i cleaned up all the wiring in the car. when i put it to gether i have a horrible whine like i have 7 turbos spooling up. i started by, removing the rca cable and running a new wire and got same issue. ran new ground to radio same prolem. ran a new power and ignition same problem. ran new power, ground and ignition from a test bench same issue. ran new power from direct battery and ground same problem. tested amp with clean power source and helped a little. tried ground loop isolator same problem. tried ground rca in front and rear same problem. in the end i touched the outer part of the rca connection of the rca to the deck and BAM all whine gone. but why i am happy i figured out the problm but what is causing it. my rca wire has so much ground in it i can run the radio ground of the rca and the damn radion turns on. the antenna is not even plugged in. so what is causing so much ground in the rca.

thanks

 

I have no idea where your problem is other then it probably is a grounding problem, I can tell you the the signal ground, ["outer part of RCA"] is a common ground, and a problem I have seen, [heard] is if an amp has had a bad or no ground, and it gets turned on, it will try and get its ground through the RCAs, and as they are not more then a tracer on a PC board in both the HU and the amp, the thin tracer blows like a fuse, in the HU or the amp or both, the result is "horrible whine" "like 7 turbos spooling up, you said that you got rid of the noise by ........<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by faiz_23 &raquo;</TD></TR><TR><TD CLASS="quote"> in the end i touched the outer part of the rca connection of the rca to the deck and BAM all whine gone. </TD></TR></TABLE> I would open the HU first, then the amp and look for a burnt tracer on PC board around the RCA connections 94

 

is the rca being ran next to the power wire

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by faiz_23 &raquo;</TD></TR><TR><TD CLASS="quote">so let me start of by saying i am a car audio installer and now i am stumpped at a ground loop issue. first i have to replace my blower motor in my car and that involved removing the complete dash. while it was off i cleaned up all the wiring in the car. when i put it to gether i have a horrible whine like i have 7 turbos spooling up. i started by, removing the rca cable and running a new wire and got same issue. ran new ground to radio same prolem. ran a new power and ignition same problem. ran new power, ground and ignition from a test bench same issue. ran new power from direct battery and ground same problem. tested amp with clean power source and helped a little. tried ground loop isolator same problem. tried ground rca in front and rear same problem. in the end i touched the outer part of the rca connection of the rca to the deck and BAM all whine gone. but why i am happy i figured out the problm but what is causing it. my rca wire has so much ground in it i can run the radio ground of the rca and the damn radion turns on. the antenna is not even plugged in. so what is causing so much ground in the rca.

thanks</TD></TR></TABLE>
It hard to make out what you are saying. You touched the outer portion of the RCA to the deck and your problem went away?

So you basically grounded the RCA? Decks and amplifiers usually use a floating ground so this is a no-no.

Since you have RCA's I am assuming you dont have anything hooked up to the deck power?

Sounds to me like the amplifier is not grounded correctly, assuming the deck is grounded properly. What kind of Deck do you have?


Modified by nsxxtreme at 1:43 AM 6/14/2005