OK, here's the deal. A few months ago, I had a Sirius unit installed in the car. It was working OK until there was a sudden decrease in audio quality before it eventually quit working. It consists of the Sirius unit, a FM modulator box, and an antenna adapter. At first, I thought it was a loose cable or something. The installer checked all the cables out and it looked good.

Next, we tried swapping out the Sirius unit. My unit worked on a different system, yet we couldn't get any other Sirius unit to work in my car when plugged right in.

Modulator box was replaced as was the antenna adapter. Finally, we replaced the cradle that the unit docks in to no avail. The antenna appears to be working normally because all of the information is being displayed on the unit. This tells me the problem is somewhere between the sirius unit and the radio. I get regular radio absolutely crystal clear.

But get this, I was just out messing with it and when I would move my hand behind the Sirius unit (which is broadcasting over FM, I can actually hear the music fade in from the static and when I move my hand away, it just goes back to static. It sounds weak and not very clear, too. Strange. Any advice?


Here's how it's installed. Cradle is mounted to a bracket:



Unit lifts off cradle:

 

Since you did multiple changes (modulator, cradle, radio) you may have to start from scratch and troubleshoot all connections - try this:

1) Confirm the FM modulator is plugged into the "FM out" jack, and not the "Line out" jack. Then confirm the FM station setting on the Sirius radio (I don't believe that cradle controls the FM station that you have to tune to and it is in the Sirius menu). Then try using the scan button on the FM radio and cycle once or twice through the FM spectrum.

2) Recheck your inline antenna adaptor plug - those small clips in the plastic housing are not very secure. It is very easy to unset those clips by sightly misaligning the connectors - the connector plugs are extremely small and the piece of the metal clip that holds it into the plastic housing can easily be unseated. Believe me the harness may "click together" and appear connected - it can be deceiving. Gently tug on the wires to confirm that they make the physical connection to the harness. (I think this is most likely the culprit). Note that it IS possible to get regular FM reception if all wires through the inline harness do not connect.

3) In both cases #1 and #2 - make sure that you turn off the internal FM modulator. When troubleshooting first have the radio on and then turn on the Sirius unit - you should hear a distinct difference in the quality of your regular FM reception when the Sirius radio is powered up - that is the confirmation that your inline FM modulator is powered up and working through the car antenna wire.

4) If all else fails try one of those cassette tape adaptors to confirm that the cradle is supplying an output from the "line out" jack. If that works at least you have the sat radio working old school style (hey its worth it to not deal with any commercials till you can get this working the way you want it to)

Side note: When you are using the internal broadcast FM modulator the reason you get that weak signal when you pass your hand around the back is because you are acting as an antenna for the signal that is coming out of the cradle. That built in broadcast FM modulator doesn't work well in most cars .