I just got a Pioneer DEH-X3500UI.
I installed it myself and matched up every wire besides the solid blue and a few others. The issue i came across is that it only receives power if i put the red and yellow wires together.

I am guessing my problem is between the red and yellow wires, since yellow is the memory wire right? That is why the head unit keep resetting?
How can i fix this since the only way i am getting power to the head unit is with the red and yellow wires connected with each other and the head unit is always resetting when the car is turned off.

Thanks

 

Sounds like you have the red and yellow hooked up to ignition power. You need to have the yellow on constant 12v+ and red on the ignition power. So just run a lead to the battery for your yellow wire if you don't have one under the dash.