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02/Factory AMP Bypass-A Simple Fix/great Results

:wave: OK I am a little lost on this The Plug I have is a Metra 80-2002 the guy at Circuit City said it is the same plug as the 70-2002 except for it has a plug on the other end that will plug in to an after market radio. I know that I just need the plug to plug in to the wiring harness after I unplug the lower plug from the factory amp and that works. The Metra 80-2002 plug has no letters on it such as A9 RF Audio- an nor dose the package that it came in so I have no idea what pin is what.
 
look at both sides of plug..... I have never seen a plug that does not have at least one number marked...

they have it for the guy who assembles the plug...

got pic?
 
:wave: I know it screwed me up I took it back and got one from another shop and it has an A & B side and No. on the pins so I think I will be OK now Well hear go's
 
:wave: Well got it done and it works fine. Now all I need to do is find time to hook the new amp to the door speakers.
 
heres a dumb question.... i have an 04 4x4 without the bose upgraded speakers, so that means i don't have the amp either correct? its just the HU powering the speakers, so if i change the HU which i plan to do as well as all the speakers ( thats why i didn't want the bose system) do i have to worry about doing a bypass anywhere? or am i good just changing the head unit and speakers will the head unit actually be powering the speakers?? thnks to whoever can answer this i'm just lost  :E:
 
Just wanted to let everybody know that I got my bypass done with the help of "butterfingarz" ( I bought his amp by-pass that he wasn't using any more ) and I can't believe the difference it made in the clarity at higher volumes. I have a JVC head unit and stock speakers. I have four Polk Audio db675 speakers sitting in the garage waiting for me to get the time to install them. I can't wait to see how much of a difference these make. Thanks to all who share info on these forums!!!!!! This site ROCKS!!!!!!!!
 
OK... so this bypass only applies to '02?  I've looked everywhere in my '03 and can't find an amp to bypass...    :help:
 
djhype7 said:
OK... so this bypass only applies to '02?? I've looked everywhere in my '03 and can't find an amp to bypass...? ? ?:help:
Click to expand...

Yup, 02's only
 
I just did it.  Bought the connector from Autozone $15.  Metra 70-2002.  It sounds somewhat better, but the factory amp (non Bose) does not have enough power at higher volumes and the display flickers with the beat of the music.  You also have to be careful since all of the protection for the speakers is in the amp.  I will try adding an aftermarket amp next.  I want to keep the factory radio since nobody steals them & I can keep all the other components out of sight. (y)
 
Well I posted my own thread but have gooten no replys!! So if someone on this one could help please. I have an 04 avy with bose, installed an after market hu since the factory hu doesnt have the RCA jacks to run to the amp. No sound obviously, I just want to know if there is any ohter way to do this besides with that harness...  I just get so confused with all of these other posts on here. There is one plug that was going into the facotry hu that wont fit into the aftermarket one and it is just sitting there.... just leave it?? I have a 1200w amp that ws installed if that is going to help at all... please reply
 
02 is different then 2004
so this thread will not apply
 
how is it different?? just the location of the amp?? I just recently purchased the 70-2002 but waiting for it to come in. The thing i just get caught up on is what do I do with the loose wires on the other end of the 70-2002?? Obviously I have to splice them into something but what?? Thank you
 
D-Loc said:
how is it different?? just the location of the amp?? I just recently purchased the 70-2002 but waiting for it to come in. The thing i just get caught up on is what do I do with the loose wires on the other end of the 70-2002?? Obviously I have to splice them into something but what?? Thank you
Click to expand...

Different in every way..

2002 had unique radio/computer communication system.

2003 to 2006 had different
So things that apply to 2002 may not apply to 2003 to 2006
 
hmm.... well i ordered that 70-2002 and I hope it will work on it!! When i get it I will first see if it fits and if not then i will have to take it back. I just want sound in my avy!!!!!! It sucks putting in subs and everything and not being able to hear it!!
 
With the Amp Bypass, you are simply creating a jumper that connects your HU's speaker outputs directly to the speaker wires going out to the speakers from the amp.  You can always trace the wires from the doors back through the wire harness to see where you can make the connections if you need to.  Everyone here is correct in telling you that the 2003's and up are different than the 2002's.  This trick may not work for you, and you may even find that the Radio and Amp have other functions such as Door Chimes and Onstar features that will no longer work when you unplug the amp.

As for my mod, it sounds much better now that I added a set of MB Quart FSA-216 component speakers.  The woofers fit in the stock door opening (drilled four holes for mounting screws) and I placed the tweeters in the A-Pillar.

My next step will be to add a powered sub.  I have already installed the adapter to the factory HU to get the line outs.

 
I'm installing an aftermarket JVC head unit, an Alpine amp, Infinity Reference speakers and wires, will I need to do the factory amp bypass? I already have the Metra harness but wasn't sure if I needed to do the bypass?
Thanks!
 
NO.... since you will have all new wiring from HU to amp to speakers
 
Finally added a Boss Bass 600 powered subwoofer to my stock HU.  It really fills my Av with good clean sound and I can keep the bass turned down on my main speakers to minimize the distortion from not having a lot of Watts to drive the speakers.  It is definitely not the Thumpin' bass you you get from a custom box with 2 or more subs and 1000 Watt amps... but I like it and I won't end up deaf.
 
I did this bypass with the Metra 70-2002 harness!  There was a bit more to it than expected from reading this thread -- mainly re-pinning the connector, but it was pretty easy to do and the results are great! 

Here is the relevant page from the 2002 manual showing the pinout:

A1 RF- Out
A2 RF+ Out
A3 RR- Out
A4 RR+ Out

A9 RF- Low level
A10 RF+ Low level
A11 RR- Low level
A12 RR+ Low level

B1 RF- Out
B2 RF+ Out
B3 RR- Out
B4 RR+ Out

B9 LF- Low level
B10 LF+ Low level
B11 LR- Low level
B12 LR+ Low level

The bypass is as simple as connecting the "Low Level" signal to its corresponding "Out" signal


CIMG4930_sm.jpg


As you can see, the bypass involves jumpering the following on each of the A, B sides of the connector (a 2x12):

1-9
2-10
3-11
4-12


The Metra 70-2002 comes like this.  This is NOT the correct pinout:
final_plug_sm.jpg


What was not mentioned in previous posts is that you need to re-pin the connector to get it to work.  I used a pick tool to release the clips and pull out the pins.  On two of them you need to solder new wires, so have some 18 AWG stranded on hand.  Basically you want 4 wires in each of the outer 4 corners of the connector, like so:
CIMG4933.jpg


And the final result should look something like this:
final_wired.jpg



There it is!  Plug this contraption into the lower plug going into the amp and you have the bypass done with no cutting into factory wires at all!

The lower plug on the amp (above/behind the glove box) is the one you want:
amp_plug.jpg

 
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