aftermarket head unit question

[markus]

i just ordered a blaupunkt bahama head unit from crutchfield.com and they said i needed some sort of adapter for my factory amp. I dont remember needing one for my M3 which basically has the same setup as my 5er. What cables will i need to hook up on the harnesses to get power to the amp?

[bimmerd00d]

if you ordered from Crutchfield, it should come with the harness for the power, and then the common ground adapter you need will be $29.99. it will come with complete instructions.

[markus]

is that common ground adapter needed? i had best buy install a radio in my M3 and it didnt need one.

[Tiger]

Markus, don't buy the adapter unless you needed it. I got same car. I installed mine just by hooking up everything to the harness... even the speaker ground. Everything works great.

Only when you hook up ground and have problem, then you got to decide. Until then, don't bother. Now I got a spare adapter with no use for it. When I was going to hook up aftermarket head unit to factory amp, I dreaded on this matter... now I just wished I just do it and then deal with it instead of dreading about it.

[bimmerd00d]

Honestly, i'd re-wire the car to bypass the factory amp, then you dont need that adapter. You power all the speakers from the blaupunkt.