my bose system uses the pink lead to turn on outboard amp. i cut off the black plug and tapped into pink lead so my aftermarket hu would work. went back to stock and of course black plug was long gone. went to boneyard and got one. only a bose car has the pink lead. i assume most of the non bose hu also have the 2nd terminal pin out but it is not used. yard had a dozen grand prixs but only 1 had bose.
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