So, I have a 2004 HSE With the Nav unit, I just pulled the non functional NAV out for a stock head unit with the cassette player in it and the radio turns on and all, but no buttons work, no volume no nothing. Are these two parts interchangeable? Also, what are the 2 coax cables on the back for? I know the bigger one is the antenna, but the smaller one?
THanks

 

I just pulled my stock radio out to replace it - seems the smaller is the antenna for he nav to me

 

I am pretty sure the small one is for the cd changer.