Audio Systems: ford expedition stereo wiring, ford wiring, memory wire

Question
Hi, my question is I am wiring a amp and sub into my factory stereo and need to know which color wires are for left rear and right rear? I also need to know which wire I can tap into for my remote memory wire. ( the blue wire leading to the amp ) Any help is good help thank you very much.

Answer
Hard to say without knowing the model and year of the expedition.  Which factory unit does it have in the dash?

For starters, take a look at this link:

http://installdr.com/Harnesses/Ford-Wiring.pdf

If your vehicle is newer than the above you may have to dig deeper.

In the worst case you will have to purchase a VOM meter (Walmart electrical section for $9.87) and trace the wires out.  If the speakers remain in the vehicle you can also use a D battery or 9v battery to check the speakers.  Touching the wires to the battery will cause a click in the speakers.  

Maybe this will help.  Hope so.
Cleggsan