I've got a 2004 Acura TL NAV. I bought the SoundGate SNHOND3 AUX-IN kit (made for the 2003 Accord) and performed the 3-wire modification that people are saying must be done if you've got a Nav system.

The SNHOND3 does seem to work and it does give me a good sounding AUX-IN, but I have the following problem:
When the SNHOND3 is hooked up I lose my XM Radio capability. When I disconnect the SNHOND3 then my XM Radio capability returns.

Anyone have any idea how to get AUX-IN on my car without losing XM Radio?

 

I need a picture of the xm unit in trunk of TL to see what type of connection harness is present. Second, the input at head unit connection harness would be a great help. The Honda Navigation unit Aux is different than non-Navigation unit and then I would be able to give you the connoctor pin out-put for the Aux/Sat if Honda has not change the wire Diagram on the Navigation System (i.e. ETM 03Accord). Im guessing here? The New XM unit is a 14 pin set-up (at xm)/power, line-out, communication link (TX-RX Honda Alpine Protocal). At Head unit 20 pin. The reason I speculate is that companies today are going to use the same equipment in as many products to compansate for profit, and employee pay. (INFO: The Honda EX-V6NV did not come with XM only 04 but software is there. reason when I say "XM Play" The system says "Radio Play" and yes, Canada is Part of the Map in Navigation System.)