Needed to upgrade the stock head unit to something that could play mp3's or take an aux unit.

Anyway - read pages and pages on here, decided quick n' cheap plug n' play swap with a Blaupunkt MP 37 London - $75 shipped off of Ebay.

Also picked up the Metra 40-EU55 Antenna adaptor.

Got both on the same day - ran around to about 3 Wally-marts before I found one that had the removal tools in stock.

Got the factory head unit out no problem.

As for the alleged Plug n' Play with the MP37 - not so much:

Plugged in - nothing, had to plug in the antenna for the unit to work at all - WTF? why does the antenna have to be plugged in? Doesn't make sense.

Anyway, got the unit to fire up, goes straight to "TELEPHONE" and won't do anything.

Ok, back to the forum, found that I had to cut the Telephone mute wire off on the factory harness - felt like MacGruber cutting the blue bomb wire - but got it figured out.

So now the unit works, sort of, think the power wires (constant and switched) are messed up, (unit turns on with the key off) - so do I need to switch those? (red & yellow)

And the big question: On the Metra 40-EU55 Antenna adaptor, there is a blue wire that looks like it goes somewhere - anyone know where? Anyone? Bueller?

 

the yellow wire is your remote (tells the deck to turn on) the blue wire would be for power antenna.
as for deck not turning on before you plugged in the antenna it probably dosen't have a ground look for a black wire or just run a ground to the harness.

 

If the unit turns on automatically when you turn the car on (provided it was on when you shut the car off last), turns off automatically when you turn the car off, but can still be operated with the key off, that's the correct behavior, and is exactly what the stock radio does. It's really convenient, great for listening to music when waiting for someone.