My xm radio on my Harley says check antenna connection,i tied another antenna and same thing,this is the 3rd time its happened,the radio works in the boom box

If you're using it with a SXV300 or SXV200 add-on tuner, there's a known issue where there's a poor connection between the antenna plug and the jack on the tuner. Plug in the antenna, then pull the cable down so it keeps a bit of tension on the plug. Use zip-ties to secure the antenna cable to the side of the tuner to keep up the tension.

If you are getting the same "check antenna" message with two different antennas, it is likely that the tuner itself is the problem. You can get just the mini tuner here:

http://www.tss-radio.com/products/xm-mini-tuner-replacement-home-dock


As far as the two plug connection, there are adapters available. Its likely a dual fakra connection, though I don't know for sure. At any rate, this is one adapter available. (I would call to confirm)
http://www.tss-radio.com/products/sirius-dual-to-single-antenna-adapter

http://www.retrevo.com/support/Delphi-SA10085-Car-Receivers-manual/id/473ag807/t/2/

click here and downlowd the file of manual.

this could be an internal problem with the unit you might also check your antenna

No experience with this issue, but in your shoes I would check the satellite antenna connection into the back of the unit. From there, I would chase the wire and make sure it is not frayed. If that does not resolve or lead to a resolution of the issue, borrow an XM antenna and see if it will work then. If not, then something has happened internally with the head unit, most likely at the antenna connection jack.

You best bet - if you can get to the rear of the XM tuner unit, is to temporarily connect a magnetic-mount XM antenna and see if it works. A bad antenna usually says "check antenna" - not loading could be a good antenna with a bad location. I would try the little XM antenna by itself, then go from there. $20 is a lot cheaper than $500. Let me know how it works out.

there saying that something is blocking the antenna. If it is saying no signal then check the connection at the unit where the antenna plugs into. If thats good then it either could be a bad antenna or a bad dock where your unit sits into.

Broken antenna cable. Likely you have a kink or worn thru point on the wire somewhere.

your sure connect antenna is bad that is why you get this message or you have something hooked up wrong check the power and ground on the unit if it has one .... some have it, some dont but most of the time its just a bad wire