Head unit problems

[Unregistered]

I'm having trouble installing my clarion vrx925vd into my 95 e34. I took it in to a car stereo service center and they said there was no power coming from (9) red/white wire which is the battery. its probably the fuse, but is this in the fuse box? I can't find it! Help!

Regards,

Bobby

[George M]

I will respond to your question
There are two +12V leads that connect to your radio. One is a constant +12V wire that allows your radio to maintain its memory and a second switching +12V lead that comes from the ignition switch. Believe the latter is the one you are referring to. First, pull up the fuse box cover and see the assignments...the radio should be among them. Check the fuse. Then take a multimeter and establish the identity of both constant +12V and the switching +12V by turning your ignition switch on and off. Also be sure to connect the thin white wire to your radio's power antenna lead that will power both the factory post amp and rear window power antenna.
HTH's Bobby,
George

[Uncle Paully]

when you say "post amp" what do you mean. why do you need to keep the factory amp when your using a new head unit that i assume will power the speakers?
thanks

[George M]

for a couple of reasons Paul...additive power and convenience of integrated cross-overs. When you drive the head unit through the factory amp in the trunk you in effect add the head unit power to the 25 watt power of the factory amp, the net effect being more power. Last reason is the X-overs for 10 speakers are integrated into the factory amplifier which has a 4 channel input from the factory or aftermarket radio. If you cut the factory amp out of the equation, now you have to independently configurate X-overs to all 10 speakers to maintain the equivalent impedance.
George