While preparing to remove my radio to fix my auxillary jack. (Missing right Channel) I noted something interesting. When plugging into the Aux Jack, the radio will automatically switch to Aux and will return to the last position when the plug is removed.

Not sure whether or not the plug is completing the ground circuit or one or both channels, but am thinking a simple electronic switch could essentially do the same.

The goal would be to build a switch that would flip the radio to Aux only when there is voltage on the line. Using my Garmin Zumo, I found that there is a .9vdc on the line when playing music.

Any electronic geniuses out there that can design a circuit to do this?

 

dont know if they can help but ....iron cross audio (in new jersy)has a good rep for doing work on the hk units.think they fix alot of cracked inputs.they will add a pigtail out the back of the unit inside the fairing .

 

If you open the radio up and look at the jack, you would see that there is a contact switch built into the jack. When you plug into the jack, it disconnects and that causes the radio to switch to AUX when there is a plug inserted.