Special thanks to Randode for figuring this one out I just want to clarify with pics.
This mod is yours and if you screw it up I’m sorry.
1. First take off the bezel around the radio 2. Remove the four 10mm headed bolts from the radio and remove, being careful not to pull the wiring too hard. 3. Looking on the back panel you’ll see the red arrows pointing to the wires being modded: a. The red/white wire (parking Brake input) b. The purple wire (VSS input) Or 4. Starting with the red/white wire. A. Cut it about 12” down the harness and tape off the harness side wire. B. make a length of wire for the grounding to the radio like this: C. I used this ground point: D. After you cut the red/white wire splice the end going from the radio to your new piece E. install the new wire now formed to the bolt with a 10mm wrench NOW WE’RE HALFWAY DONE!!!! 5. The purple wire A. I installed a switch in one of the blank panels by the trac control B. Add to lengths of wire about four feet long to each post of the switch C. I routed the wiring thru here, popping this panel off to gain better hand access D. Routing the wires up thru the dash to the back of the radio I cut the purple wire about six inches away from the radio while the connector was unplugged. I then stripped the wires and added the purple wires to the two wires on the switch. E. It doesn’t matter which side the wires go on; Then I put the whole thing back together and now can have a passenger use the navi controls while I drive or watch a movie or whatever.
With pioneer units, they tend to be a quick and easy bypass. On my older model its just one wire. Which I have sent to a switch (much like you did) then the the radio ground). And since Pioneer usually has to see no ground before the radio is on, you have to use the switch. Low end units (Jensen/Dual) you can usually just ground the parking brake wire to the radio ground, and never need a switch.
This is a good write up however. I am sure some people will be doing this very soon.
Once I order my AVIC D3 from Pioneer I will do the super easy write up on how to make those work while driving.
