Crazy Car Audio Interference

[adv4nced53]

So here is the breakdown:

I'm running an aftermarket deck, a 4-channel amp for the speakers, a small subwoofer, and a 2-channel amp for the sub. From the day I installed it, there has been a little bit of interference (whine), which never really bothered me.

One day, I went to the track and took my sub out to save weight. After a few hard launches and whatnot, I came back and wired the sub back in. In the process, I managed to short out the power wire to the sub on the sub amp. When I turned the radio on, the interference was horrible!!! (very loud whine)

I figured I shorted the 4-channel amp, so it took me a while to test stuff. So this is what has been tested:

- Removed the sub and sub amp to eliminate them as the issue
- Tested the deck on another car on which the deck powers the speakers. The car was turned on.
- Tested with different RCAs...no difference.
- Tested with a different 4-channel amp. Interference went down substantially but it is still way louder then how it was before.

I assume it is either a ground issue or the amp even though the good amp also tested with whine. The radio whines when the ignition is in the ON position, without the car running, so it is not the alternator. When the ignition is in the auxiliary position, everything sounds perfect, except when something electrical is working...such as the antenna going up and down or the lights dimming when I close the doors.

Any input is appreciated and sorry for the long post.

 

[ryguy86eklipse]

I've had a similar issue myself but on a lancer. One thing I would do is double check your grounds and make sure they are in fact grounds. This will help in more ways than one. Are you running a rewired fuel pump which connects to the amp wiring?

 

[adv4nced53]

The fuel pump is on the stock wiring. I checked the grounds and even moved them around. I was just outside playing with random electrical components to see if they have anything to do with the interference...found nothing.

 

[boostin92awd]

Definately a ground issue. I had the same problem I had to keep searching around for a better ground I couldnt take the whine any longer.

 

[adv4nced53]

Definately a ground issue. I had the same problem I had to keep searching around for a better ground I couldnt take the whine any longer.

Right...but that's not the problem here or at least not entirely because it happened all of a sudden after working fine for over a year. IF it is the ground, what could have possibly happened that would make the ground (chassis) get interference? All my other devices seem to ground properly and they're all grounded near the deck.

 

[boostin92awd]

Ive had grounds that have came loose over time before. Or possibly your ground wire is damaged in some way. I would just go throught it checking the wires and maybe even try new ground sources.

 

[jayiszraw]

ha its the grounds, check the grounds on the battery, and amps also make sure its a true metal to metal ground (scrape paint off for best results) also aree your rca cables running next to your power wires? trry running them on opposite sides. also make sure tha radio outputs are properly grounded, some aftermarket radios are known for crappy grounds (pioneer) so i recomend trying something like this:

You must be logged in to view this image or video.

Thanks to Ultimate157 from caraudio.com for the image.

let me know how it works out.

 

[boostin92awd]

ha its the grounds, check the grounds on the battery, and amps also make sure its a true metal to metal ground (scrape paint off for best results) also aree your rca cables running next to your power wires? trry running them on opposite sides. also make sure tha radio outputs are properly grounded, some aftermarket radios are known for crappy grounds (pioneer) so i recomend trying something like this:

You must be logged in to view this image or video.

Thanks to Ultimate157 from caraudio.com for the image.

let me know how it works out.

Awesome idea Yes definately scrape paint for better ground as stated above.