Hi, I am new here and I need help. I just acquired a 1990 Mazda RX-7 GXL and I need to know what the wiring schematics are for the stock radio that is in it. I have a Sony MD deck that I want to put in but at first sight I see that the stero in the RX-7 is going to leave a pretty big space after I put the MD player in. I am relatively new to the RX-7 scene (this is my very first one) and would welcome any advice/solutions. Thanks!

 

Ok, to install the Sony MD headunit, you'll need a harness adapter and install kit.

I've just mentioned this part number before, but since the harness adaptor is different, I'll post it here.

You need:
Manufacturer: Metra
99-7501 (headunit installation kit, single din)
70-7901 (wiring harness adaptor, into CAR)

Follow the instructions, match the wires of the harness to the wires of your deck's harness, solder or crimp and just plug in.

You will need to connect the ground wire or the unit directly to a metal bolt or screw (the harness doesn't have a ground). There's a panel to either side of the stereo that can be removed, removing them should reveal a 10MM bolt that should serve the purpose perfectly.

If the plugs for the stock radio were cut, you'll need:
71-7901 (harness into OEM RADIO)

As for the a schematic of the radio wiring (if you need it), you can download the wiring diagram section of the car's factory service manual from www.fc3s.org --how to--manuals

Be sure to download the section corresponding to the 89-91 model year, which your car falls under, NOT the 86-88 model year.

Oh, and you can fit 6.5" speakers in the doors, up to 6" in the rear shock towers, and 4" in the dash board.

Enjoy.

 

Oh, and one other very important thing: the proper removal of the stereo/logicon trim piece. If you go too fast and force it, you could break it, and it's expensive to replace it (though it is made of a better plastic than the earlier 86-88 one, I still need to replace mine).

The trim is attached to the dash by screws at the top and bottom of the piece. You need to remove the vents at the top (they snap out) and you'll see some philips screws. At the bottom, pry up the shifter surround, and push it out of the way.

Also, pop open the ash tray and lift it out. Behind the ash tray, you'll see two more philips screws. Once they are removed, the trim piece should come off easily (go slow, and remember to disconnect the ciguar lighter plug).

The headunit stack is held in place by four philips screws. Remove them, and pull the whole assembly out, and be sure to d/c any harnesses and the antenna plug.

Volia.

 

You will also have to install a relay for the power antennea to work properly.

 

Something which I forgot to mention because I replaced my factory antenna with another unit.

 

Hi, I'd like to jump in late on this month old thread. I have an '86 and the stereo was stolen and all connectors cut off with it a couple months ago. I'm trying to make sense of the loose, exposed wires in the gaping hole so that I can try to get some music back in my car by installing an after market stereo. I really appreciate the information supplied by Cluosborne, particularly the link to the schematics. This certainly gives me a place to start. Things make much more sense now though it's added some confusion too. For one, the audio sections of the "body electrical system" and the "wiring diagram" don't seem to agree. The former (for ex. page 15-116) mentions only front and rear speakers. The latter (for ex. page 50-96) always makes mention of also door speakers (which I've completely overlooked if I've got 'em). Either way, there appear to be two speaker bundles. One with brown and blue wires and the other with light green. My best guess is that the blue/brown goes to front speakers and the light green to rear. Or am I completely misunderstanding the whole concept here?

Thanks!

 

This subject has been covered quite a few times, you may wish to use the search function found in the upper right hand corner fo the page.

I also do not recommend the mounting kit that Clousbourne recommends, but suggest that you use the stock mounting brackets if available, (as they will provide much better mounting that the plastic kit can do) and a simple custom trim ring. The plastic kits do sag after time and are more prone to causeing mounting problems down the road.

Again if you search you will find the pictures of this as well as how to wire the antenna relay that will be required for operation of the staock antenna by an aftermarket radio, and of course the aftermarket radio wiring to stock wiring.

 

I would agree with the mounting kit. I just used it because I didn't have the factory stereo, nor was what was there well-installed.

I just went with the plastic kit because I wanted a quick way to install another headunit I wanted to use for a short time. If I had the factory brackets, I certainly would have used them, and I recommend the plastic kit ONLY if your car's factory stereo was missing and you didn't want to go through all the hassle of fabrication and finding a set of brackets (though it shouldn't be hard to do).