If I swap head unit, will I lose bluetooth?

If you are swapping to an aftermarket stereo that has bluetooth and Nav then you lose nothing but steering wheel controls and even those can be retained with the right adapter module. Yes you can integrate an aftermarket head unit with the JBL amp system.

 

The blutooth is apart of the MFD and communicates directly with the JBL amp under the passenger seat.

 

The MFD controls the Nav and the blutooth and the blutooth module is physically inside the MFD. Now the real question is will the Nav and blutooth audio still function with the head unit removed. They should work since neither the wiring or the network communication rely on the headunit for the connection between the JBL amp (and the speakers) and the MFD. They only way to know is to unhook the headunit, insert the proper resistor in the network loop for the missing headunit and try it out.

 

I apologize for not knowing anything about the NAV and bluetooth portion of the Prius. I don't know how they are wired.

With my install method, the factory stereo will still power up but you are changing some of the wiring around. One way to test if the NAV and bluetooth sound will still work when the factory stereo is effectively removed from the picture is to disconnect the speaker wire plug (the smaller of the two that go in the back of the stereo) and see if the sound still works. With my setup you will still have the factory stereo in-line with the Canbus system so you don't have to use resistors but you will not be using the stereo for anything else. The speaker wires that normally plug into the factory stereo will not be plugged into the new aftermarket stereo wiring harness.

To answer your question, you need to purchase two wiring harnesses. There is the standard "aftermarket to factory" (Best Kits - BHA1761) stereo wiring harness and there is a "factory" (Best Kits - BHO1761) style harness which normally is not used in the installation of an aftermarket stereo but in this case we need it to power up the factory stereo so we don't have to use resistors. I wish I had the camera angled better when I did the wiring part but I didn't notice I was out of the screen until long after the video was shot.

Wiring:

1. Connect the red wires from each harness (BHA and BHO) together in one side of a crimp connector. Leave the other end open.
2. Connect the yellow wires from each harness (BHA and BHO) together in one side of a crimp connector. Leave the other end open.
3. Connect the black wires from each harness (BHA and BHO) together in one side of a crimp connector. Leave the other end open.
4. Connect the red wires from the aftermarket stereo harness into the open end of the crimp connector containing the red wires from step #1.
5. Do the same for the yellow and back wires.
6. Connect the remaining wires on the aftermarket stereo harness to the corresponding wires locate on the BHA wiring harness (this includes illumination, speaker wires etc.).
7. Once all of the wires are connected you simply plug the aftermarket stereo harness into your aftermarket stereo. The BHA harness into your factory wiring harness that comes out of the dash. The BHO harness into your factory stereo.

*Note- Sometimes the AC error will pop up or the MFD will go blank. This is fixed by simply unplugging the wiring harnesses and plugging them back in. Please check for this condition before putting your dashboard back together.

I will do my best to get to the stereo shop and actually take pictures of the harnesses all wired up to make this more clear. It is actually VERY easy to do but difficult to explain. I'll also go in and update my original thread.

 

Ok, I have a buddy at the shop who is going to take a picture of the wired up harnesses for me hopefully today. Stay tuned!