I have a AVH-X 8500 BHS and I cannot get to the Bluetooth settings they are greyed out and I just got a galaxy s5 so I want my Bluetooth to connect. I cant remember how we did it on the galaxy s4.....HELP

you have to ground the parking brake cable in order to be able to access those settings 

Thanks for the info.  I've been looking for this answer for about 2 months!

Well, this answer didn't really fix my problem.  I was able to ground the parking brake wire and i could tell it had an effect on the unit because I was able to play a DVD in it.  However, I still could not access the bluetooth settings as they remained greyed out.

What I'm trying to do is erase whatever's stored in there so I can pair it with our phones.  We installed it brand new and when we were playing with it, we paired it with 3 other devices (not the ones we want).  Now I can't clear them out to pair the valid ones.

I'm looking for some way to completely erase/factory default the unit.  The reset button clears the programmed stations and the date/time but not the bluetooth.  

Any suggestions?  Thanks!

Also this is an avh-x7500bt model if that matters.

These units can behave strangely if the USB connector is attached.  I forget the exact sequence of steps in my AVH-5600BHS, but I remember it being a PITA to figure out and through trial and error I was able to disconnect the USB cable from the phone, then shut off bluetooth, then restart the radio, then the choice was no longer grayed out.  Something like that  Good luck!

I have a AVH-X 8500 BHS and I cannot get to the Bluetooth settings they are greyed out and I just got a galaxy s5 so I want my Bluetooth to connect. I cant remember how we did it on the galaxy s4.....HELP

Add a switch to the parking brake grounding. Turn switch on and off and see what happens.

I had a similar issue.

Radio <--> green cable <--> switch <--> ground.