View Full Version : Radio Diagram help???

03-12-2005, 10:16 PM
1 I know what the dimmer is, what is the Memory?
2 Why is there a power antenna in addition to the antenna cable?


3 I'm aware that the amp power wire is not shown, are there any other wires not shown that I will need to hookup?

4 What are these cables?


03-12-2005, 11:18 PM
1) Memory is non-switched (aka - direct to battery...maybe with a fuse between it, I don't know) power source that provides juice to the head unit so it remembers presets.

2) Most of our cars (mine, at least) has a three antenna system and a computer to decide which antenna, or combination of them, is used. That computer is turned on or off by that lead. Additionally, it turns the stock amp on or off.

3) need to hook up the Amp ON from the head unit to the aforementioned power antenna lead

4) common grounds for the speakers (note how you don't see a negative for each of the speaker leads on the stock head unit, but your aftermarket has them).

best, whit

03-13-2005, 12:20 PM
Yes, memory ougth to be a permanent positive, always trough a fuse. BMW standard wiring have this wire.

Power antena is normaly used to rise/lower the antenna , I have one of those in the Jeep Wagoneer. If so, it will only gets power if Radio is On.

As for the Power Amp wire, there is none, as I see no sound (RCA) outputs for amp here, if the only available outputs are intended for speakers, you will have poor sound quality, hooking them into the AMP input.


03-13-2005, 01:09 PM
Ok, I would like to try the RCA's as well as the harness to see witch has better sound quality. The HU I'm looking at has 2.7 volts out of the rca's so that might work with the stock amps 5 volt requirements.
On the bmw, I will soilder all the positive leads (that go to the amp) to the center of new rca connectors.

On the new HU harness: I soilder all the positive leads to the center of new rca connectors, and ground all the negative leads to the grounding wires?

For the RCA's coming off the new HU: Do I leave the negative part of the rca's untouched, or do I ground those?

Purpose being, so I can simply unplug the 4 wires from the harness and plug them into the rca's for a quick sound quality check.

03-13-2005, 02:02 PM
connect all of your aftermarket negatives to the common ground unless you're running RCA's or an aftermarket amp, both of which are recommended).Not all decks will survive if you common their powered grounds - most decks have very explicit warnings in their installation manual warning against this.

Even though you could probably get around it with creative wiring; running a box like a PAC OEM-2 (http://www.crutchfield.com/ISEO-rgbtcspd/cgi-bin/ProdView.asp?g=751&I=127OEM2) would make a lot of things easier (and likely to work), and wouldn't risk damage to the new headunit.

If you look around, you can find it for a bit less than Crutchfield.

03-13-2005, 02:47 PM
That looks great!
Would you recomend hooking it up with the RCA's or the harness?

03-13-2005, 04:56 PM
That looks great!
Would you recomend hooking it up with the RCA's or the harness?Though I can't say for certain, the RCAs there are probably for connecting a factory deck to an aftermarket amp.

In your case, you'd probably use the speaker (line) level output of your deck, and use the four pots visible on the box to adjust power. This way, you can (probably) match whatever signal voltage the factory amp wants.

It should come with plenty of instructions that are probably going to be more useful than me. :)

03-13-2005, 07:02 PM
GOOD info...I didn't know that...

best, whit