Head Unit Installation

[mauidiver15]

Hey there,
First time I've ever touched anything audio. I just bought an Alpine 9821 head unit (deck) and I want to know any precautions about installing it. Can I just pull the old one out, unplug cables and plug them into the new one? Or is there something I need to take care of other than that. The new Alpine has a built in 4 x 45 amp so do I need to disconnect the stock amp if there is one? Seems to me like I've read before that the stock explorer has an amp built in near the right rear speaker. I have a 91 navajo. Thanks for any tips guys, cause I'm lost with this stuff.

Thanks

 

[thewishkah]

Ok you will need a wiring harness for the amp unless you want to run new wires or by an amp bypass harness if you can find one . If you just dissconect it your speakers wont get any sound cause the speakers run to the amp then from the amp to the radio.

 

[huskyfan23]

You'll need to buy an adapter harness to plug in stock to Alpine, or cut the stock harness and wire to the Alpine harness. You'll get sound if you connect the remote lead from the amp to the remote lead on the Alpine.

 

[mauidiver15]

ok, so I'm not sure what I should be doing. In responce to the first post, I realize I can't just unplug the amp, because its inbetween the speakers and the head unit, so I of course would not get sound because the speakers would not be connected to the head unit.

What I don't understand is this new harness I need to get. Can I just bypass the stock amp because the new head unit has one built in and run wires from the deck to the speakers? Or do I get an adapter and leave the stock amp in the system? These things I don't understand.

Thanks

 

[barneyrubble318]

There is an amp by pass wire harness you can buy. You unplug the 'in' at the amp and the 'out' at the amp. This harness joins the 'in' and the 'out' leaving your stock amp unplugged. Now your Alpine will use the stock wiring in your truck, bypass the amp, and go to your 4 stock speakers.

 

[huskyfan23]

Yes, there's the amp bypass, which is not necessary, it just allows you to run off your HU's preamp. The harness I was talking about is an adapter that plugs your existing harness into the Alpine unit. You didn't sound like you wanted to wire so I brought it up. If you don't want to cut your factory harness then you will need this kit: http://www.crutchfield.com/S-heDK19C2eSK/cgi-bin/ProdView.asp?g=103000&id=essential_info&i=120705004

 

[mauidiver15]

Ok, the amp bypass harness seems like an easy and reliable fix. Where can I find this? If I do this, are there any other changes that will need to be made? Do the wires that plug into my stock head unit also plug into the Alpine? Or do I have to also get the adapter kit that huskyfan linked me to? Also, isn't using the Alpine internal preamp plenty for stock speakers?

If I plug the existing harness into the Alpine unit like husky fan mentioned, is it ok to have both the alpine amp and the stock explorer amp working at the same time?

I am a person that likes quality and reliability. While I know the new Alpine isn't top of the line, I don't need insane sound, I just wanted a cd player that is installed correctly. Considering that I don't want super loud sound, but I want a quality installation, what method would you guys recommend for this installation?

Thanks for the help and bearing with my complete lack of knowledge here.

 

[huskyfan23]

The amp bypass is excellent for crisper sound and less distortion at higher volumes. Your factory Ford harness WILL NOT plug into the Alpine. If you don't want to cut your factory harness to wire it to the Alpine, you will need the kit I linked you to. You can't run the factory amp with the preamp in the Alpine, one or the other. The factory should also never be used with an aftermarket head unit.

 

[mauidiver15]

Does the product you linked me to come with both the adapter to the harness and the amp bypass? Just want to make sure I'm getting the right thing.

Thanks

 

[barneyrubble318]

Yep. It has everything you need. The notes say it has the bypass harness. The picture shows 3 different harnesses. The left one is the amp bypass. The middle one is for the power, ground, remote on, etc. to your new HU. The right one is for the speaker connections to your new HU. $20 seems like a good price to me.

 

[mauidiver15]

thanks for all your help guys

 

[expo5.0]

you CAN do it all without any harnesses or kits if you don't mind splicing too...

but the harness will make it easier