need help installing an aftermarket stereo

[Maztang]

my brother has a 1991 mr2 and i am having a hard time trying to figure out what harness to get. the factory harness is a 14 prong harness. i read the sticky on here a few minutes ago and it is very knowledgable but isn't helping me for this reason...

first we bought harness part number 70-1761 from best buy. there were 2 harness in the package. we get home and pull the radio out just to find out that it has only 1 harness. so we take it back and the guy asks us if it has the jbl system. he says that without the jbl system there are only 4 speakers and with the jbl system there are 7 speakers. well my bro has the 7 speaker setup, so he gives us another harness. but this harness is small, the 2 harnesses won't connect. the 2nd harness that he gave us was part number 70-8112. where am i going wrong? am i supossed to connect the harness somewhere else? i couldn't find where to connect it so if anyone knows please help me out. thanks.

[biorchang]

It might help if you could post some pictures of them.

[Maztang]

that was the first one that we got.

i am trying to find a good pic of the other one

[Maztang]

and this is the 2nd one that we got. don't know which one it is supposed to be if either?

[Maztang]

this is the 1st one we bought...



this is the 2nd one...

[eckoman_pdx]

You should have the Factory Premium Sound System, which consists of 7 speakers for a 91-92: 2 tweets in the front, 2 4" speakers in the front, and 2 2.5" speakers in the rear, plus a 5.25" woofer in box.


70-8112 should be the correct harness. The first harness won't work. The second one should plug into the OEM plug, and it will allow you to still use the factory amplifiers. It should plug right into the OEM plug that went into the back you the factory premium sound system.

It should look like this, which is the second one you posted. I just looked at the back of my factory 92 premium radio, and it's a 15 pin connector and looks identical to the metra 70-8112 connector.



Here is the wiring pin out for the harness, which will tell you which pins/wires on the Metra harness do what. Connect the proper metra wires to the proper radio wires, and plug the RCA's into the RCA outs on the aftermarket radio. The below Diagram tells you which RCA plug goes where on the aftermarket radio.




I didn' t bother using a harness when I put an aftermarket radio in mine. I by-passed the factory harness, factory amps, and factory wiring entirely.

[MR2 Drifter]

I thought all MR2s had the 2 tweeters, 2 front speakers, and 2 back speakers.
And if you had the premium you also got the subwoofer that sits behind the drivers seat

when i bought my MR2 it didn't have a radio =( my wirings like the 1st one, even tho there was a bunch of cut wires and wires running toward the back (like it was connected to some subs)

How far back do the wires go? I was just thinking of getting a whole new radio wiring harness and replacing all the wires and speakers with some sony ones

[Maztang]

Originally Posted by eckoman_pdx

You should have the Factory Premium Sound System, which consists of 7 speakers for a 91-92: 2 tweets in the front, 2 4" speakers in the front, and 2 2.5" speakers in the rear, plus a 5.25" woofer in box.


70-8112 should be the correct harness. The first harness won't work. The second one should plug into the OEM plug, and it will allow you to still use the factory amplifiers. It should plug right into the OEM plug that went into the back you the factory premium sound system.

It should look like this, which is the second one you posted. I just looked at the back of my factory 92 premium radio, and it's a 15 pin connector and looks identical to the metra 70-8112 connector.

http://www.meiyuservice.com/Images/t...15pininter.jpg

Here is the wiring pin out for the harness, which will tell you which pins/wires on the Metra harness do what. Connect the proper metra wires to the proper radio wires, and plug the RCA's into the RCA outs on the aftermarket radio. The below Diagram tells you which RCA plug goes where on the aftermarket radio.

http://img384.imageshack.us/img384/5...trapinslr9.jpg


I didn' t bother using a harness when I put an aftermarket radio in mine. I by-passed the factory harness, factory amps, and factory wiring entirely.

yeah, i would think that this one would be the one as well but they don't connect. i don't know why. i can not get the oem plug to fit inside the adapter at all. i am at a loss right now.

[eckoman_pdx]

Originally Posted by Maztang

yeah, i would think that this one would be the one as well but they don't connect. i don't know why. i can not get the oem plug to fit inside the adapter at all. i am at a loss right now.

How many pins does the OEM connector have? I noticed the 15 PIN Metra harness says "92-99" on it. It's possible the 91's had a connector that differed/had a different amount of pins than the 92+ premium systems.

I just looked it up in the 91 MR2 wiring diagrams, and it looked like it was 14 pin on the radio side. Not sure. Count the number of pins on the OEM connector, take a picture of the OEM connector and post it.

You may end up having to install the aftermarket radio by by-passing the OEM wiring/connectors entirely. If you do this you'll by-pass the factory amps also, and be running off deck power.

[Maztang]

yeah, this 91 has the 14 pin. i didn't want to bypass the harness, i just wanted to plug and play, but it looks like that is what i will have to do. if he wants me to anyways. everywhere i have looked shows one of those 2 harnesses so i guess i will be cutting the harness and wiring it all in without an aftermarket harness. thanks for the help.

[eckoman_pdx]

Originally Posted by Maztang

yeah, this 91 has the 14 pin. i didn't want to bypass the harness, i just wanted to plug and play, but it looks like that is what i will have to do. if he wants me to anyways. everywhere i have looked shows one of those 2 harnesses so i guess i will be cutting the harness and wiring it all in without an aftermarket harness. thanks for the help.

It looks like it's the ACC wire is the one that's missing from the 14 pin harness on the 91's, it connects somewhere else to it all. You could always try to get a 14 PIN connector, and extract the pins from the 15 PIN Metra, and put them all in the proper spots in the 14 pin connector. You'd have to wire the ACC wore up separate, but you can just tap into the ACC on the cig lighter socket for that. Maybe use male-female disconnects on the ACC and all the radio to harness wires, so it's easy to disconnect, remove and redo if he gets a new radio ever.

IDK, this might be more work and trouble than you want, but it would give you an actual removable harness the for 91 with premium stereo.

When wiring it in with no aftermarket harness, I wouldn't cut the OEM harness, I'd just bypass it all 100%.

[downsouthdub]

i just installed a new head unit in my brothers 91 turbo, and we could not find a harness for it anywhere. we ended up bypassing the factory amp and ran new speaker wires to the speakers (the head unit has a built in amp and we did not find a need for the oem one). the speakers inputs for the factory amp share the negitive wire at the radio plug, and if you connect all the negative speaker wires comming out of your new head unit you could short the internal amp out... so you kinda have to run new wires unless your h.u. does not have a built in amp, wich im sure it does
hope this helps and is not too confusing

[eckoman_pdx]

Originally Posted by downsouthdub

i just installed a new head unit in my brothers 91 turbo, and we could not find a harness for it anywhere. we ended up bypassing the factory amp and ran new speaker wires to the speakers (the head unit has a built in amp and we did not find a need for the oem one). the speakers inputs for the factory amp share the negitive wire at the radio plug, and if you connect all the negative speaker wires comming out of your new head unit you could short the internal amp out... so you kinda have to run new wires unless your h.u. does not have a built in amp, wich im sure it does
hope this helps and is not too confusing

There's another way to do it too. I forgot which harness works (what car it was actually for), but there is a harness that plugs into the speaker output plug if you remove it from the amp.

If you run the aftermarket HU's speaker wires to the back, and crimp them to this harness plug (I forget what you need to buy), you can plug that harness plug directly into the speaker output plug you removed from the amp. That allows you to bypass the amp 100% without running any new wiring. If you do this, might as well remove the amp from the car as it's just dead weight. However, running new wiring is always a good idea, as OEM wiring is usually a joke. Besides, with the MR2 cabin being so small, it doesn't take much wiring to run new stuff.