Strezzd

The "Metra 70-8112 radio wiring harness for Toyota Amp Integration 15 Pin" (**edit** see below) worked with my Pioneer AVIC-8200NEX using the factory Nakamichi system setup. All four speakers worked as well as the subwoofer (powered by the single amp under 12 CD changer). I have a 1998 SC400.

I'm not sure if Metra changed their harness since Raine's original writeup but it does work now except there is no illumination wire on the Metra harness. My car is still apart so I have not driven it yet but I hear no alternator whine (yet) while revving the engine. I ran 6 RCA's to the trunk already because I couldn't get the RR speaker to work and thought the Metra harness didn't work but it turned out that the speaker was dead-dead, so I guess I'll leave the RCAs for a future project.

**EDIT** A new Metra harness showed up today that was not modded during my attempt to find the bad speaker I mentioned above. I ordered it to confirm it was just a bad speaker. It turns out after using this new, unmodded, Metra harness that the FL(driver's) speaker did not work. I returned it to the modded Metra harness and all is good again. The only mod to the the harness was cutting the extra ground wire that went to each of the 4 RCA's and separating the grounds (bare strands) connecting the four RCAs (requires some removing of the sleeving on the Metra harness). See below photos.


Top - Cut ground and removed shared ground between 4 RCA's (not observable)
Bottom - Original Metra harness.




Background

rickashay

Wow thank you for the response. I parked my SC for the winter and left the stereo pulled an the dash half apart, with plans to post-pone this project. Just diving back into the details as a refresher and will be tackling this in the next couple weeks. It’ll have a look at my harness and follow your lead on the grounds. Initially when I first tried my HU install with the Metra, I just wired it as I would any other aftermarket HU, matching the colours to the harness etc. I plugged it in hoping and expecting that it would either work fully or some components would work correctly. Unfortunately for me, the head unit would not even turn on. It’s been too long now for me to elaborate more than that.... but I hope I can get it going and your response has given me some hope! Did you get all the speakers working properly?

Bala501

Hey guys, running into a bit of an issue i'm having trouble solving. I hooked up my head unit as per the guide, bypassed the amp and everything else but for some reason the head unit won't actually power on unless the amplifier is plugged in, wondering if maybe the radio gets it's on signal from the amplifier being powered on? Makes no sense to me since everyone else had luck.

pishta

This is exactly what I was looking for! My kids 92 SC is on its 2nd Pioneer and I just managed to install a Farenheit EFM-02 FM modulator to allow him to listen to his aux in phone music. I got him a double DIN Kenwood NAV/DVD/CD/SAT/HD whole enchilada and a Metra bracket. I dont even think I need the Metra bracket as it looks 95% like the stock metal one? Im not certain the sub amp even works, FM sounded like ****, but the CD sounds great? Could the FM not be turning on the sub? Im probably going to install an old 100Wx4 amp in the back and maybe a 200W bridged 2CH amp for the sub if its bad. All in the trunk where the CD was.

pishta

I-1 clarification. I just did this and the '93 subwoofer grill is on REALLY tight. Pry up the corner to see the metal clip and put a very wide blade screwdriver between the grill and the clip base NOT THE FIBERBOARD, IT WILL BREAK! Turn screwdriver to pop it off. My 10" sub cone was gone. Only the coil cover was there! Is there any way to tie into the heave front speaker feeds from the radio area or do they run up the sides? Seems a shame to run 4 pairs back to use the factory 2 pairs up to the front again. I could not locate them in the harness behind the stereo.

pishta

Yellow is 12v+, red is switched on ACC 12V+. That seems backwards to me but thats how it is.

pishta

FYI the factory amp under the changer is only 30Wx4 (2 Toshiba TA8221AH in parallel) so dont be afraid to bypass it with a higher power head unit. The Kenwoods typically have 50Wx4 out. Anyone know the Sub amp power or stock Sub (92 Pioneer 10") power rating?

JustaGE

I wired everything in awhile ago, and most of it is working great. Touch screen JVC head unit, universal wiring harness. My speakers work and the head unit works, but I have to turn it on and off every time I use it. The radio also drains my battery over time. I have the red wire from the radio connected to the grey wire in the car, and it doesn’t work. I’ve tried different wires and nothing seems to work. Anyone have any guesses?