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MogaJeep 10-13-2012 11:22 AM

Radio Interference: Help!
I have the Infinity audio system with the 10 disc changer. It has the amp under the rear seat.

My headunit is the RAZ version MOPAR P/N 56038555AM

Here are the symptoms:

When the Jeep is running I get random interference (ticks and pop sounds)

The interference IS NOT related to RPM range. It doesn't increase/decrease with an adjustment of RPMs.

It is not static

Happens on FM, AM band all stations, ALSO on CD

DOES NOT happen when motor is not running

The ticking and popping is present 90% of the time, sometimes it goes away, sometimes it is barely audible, sometimes it is loud.


- I went to the junkyard and they let me try another head unit. Thinking maybe the head unit was bad. The one they had was fully functional.
The same interference was present. :mad:

I guess it is a safe assumption the headunit is not the issue. But, what if that head unit also had the same problem as mine; since it isn't brand new I guess that is a possibility. :confused:

- Battery terminals are clean as a whistle. Wiring looks fine. Battery is fine and charges fine. Keeps 12v goes to 14v on acceleration.

- Radio wiring looks perfectly fine. I shoke the wires played with them, fiddle with the connector, etc. Everything is tight and in order and did not solve the problem.

At this point I have no idea what to try next and any help/experience is greatly appreciated!!!! :thumbsup:

Frango100 10-13-2012 02:19 PM

Re: Radio Interference: Help!
Eventhough the interference is not rpm related, i would have a look at the alternator. You could remove the accessory belt and run the engine for a short time ( the water pump will also not be driven, so keep it short, 10 sec. or so with a cold engine. You will probably get the check engine light, which has to be reset afterwards). If the noise is still there, its obviously not the alternator.

hoffmanestates 10-13-2012 02:45 PM

My cousin has this issue and he has a sound system. We had to replace alternator. New wires cables.and on motor there are ground straps and these black plugs that are for radio interference

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MogaJeep 10-13-2012 04:28 PM

Re: Radio Interference: Help!
Thanks for the ideas. I'm gonna have to check out the alternator tomorrow because the Jeep is not cooperating.

After testing a different head unit and looking over the ground connections, and the amp the Jeep has decided to enter "cannot reproduce problem" mode :lol: and has stopped getting interference.

I swear sometimes I feel like this thing just wants the attention and after you chase the problem it's like "ehh, I'll stop being annoying now."

If it is as easy as changing the alternator I will be really happy.

Oh also aside from the interference sometimes the music volume will fade slightly from certain speakers and come back. What I mean is the fading is not equal through all speakers, it kinda fades in and out like a warp effect.

It's a separate issue from the interference but what could that be? The amp, maybe a sign the head unit has seen it's days?

MogaJeep 10-15-2012 07:48 AM

Re: Radio Interference: Help!

So the alternator is not the problem. My buddy recently replaced his alternator on the same Jeep. So I took his out, and installed it in mine to see if the interference was still there. It was. (I know, not the way I thought I'd be testing the alternator theory either haha)

Next on the list is to inspect the length of wiring from the alternator and all ground connections/wiring dealing with the radio.

I'm thinking it has to be a bad ground at this point. Any thoughts?

Frango100 10-15-2012 08:18 AM

Re: Radio Interference: Help!
Have a look at the speaker connections as well. Could be that the amp is on its way out.

MogaJeep 10-15-2012 08:56 AM

Re: Radio Interference: Help!

Originally Posted by Frango100 (Post 697066)
Have a look at the speaker connections as well. Could be that the amp is on its way out.

Thanks, you're right a speaker wire may be loose. I was thinking about the amp too. Afterall it is 8 years old probably burned out.

Is there anyway for me to test the amp to see if it is shot? Other than buying another amp and trying it?

Saquui 11-29-2012 09:31 AM

Re: Radio Interference: Help!
Odd. I have a liberty and have been having the same issues for the past few months. For about the past year, every time I turn my blinker on the overhead light comes on. Any ideas on how to fix this or what the problem may be? Thanks!

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