switching factory deck

For everything related to the inside of the car!!

switching factory deck

Postby lamard » Sun Aug 08, 2004 8:21 pm

Hi guys, I went to switch my factory deck (with the system 10 package) and found out that I can't buy a harness. the guy said I would have to rewire it and I would probably lose 2 of the speakers, as a deck only has four channels. He also said something about bypassing the factory amp. Just curious as to what some of you guys did.

Members don't see the above ad. Register now - it's free!
Club Member
Posts: 105
Joined: Sun Aug 08, 2004 8:17 pm

Postby Shaggz00 » Mon Aug 09, 2004 12:50 am

never worked on the system 10, seeing as how I have a 165, but from my limited knowledge I'll try and explain whats up.
The reason that you will be losing 2 speakers is because the aftermarket head unit only has outputs for 4 speakers unlike your factory unit which has more outputs(again, I never worked on one, so I dont know how many).
The reason that they need to do a rewire to bypass the factory amp is this:
A stock head unit puts out a low wattage signal. it needs the amplifier to boost that signal to a normal listening level. An aftermarket head unit already has an amplifier built into it. therefore there is no reason to use the factory amp, because your factory speaks wont be able to handle the wattage.
I guess the ghetto thing to do to keep all your speakers would be to splice those unused speaker lines into used speaker lines after the install. I wouldn't really recommend that seeing as how it would cut the power to those speakers.
Hope I helped a little bit.

BTW, yes, a amplifier bypass will be expensive, because the shop won't(or should not) use the factory wires. the correct way to do it is to run new wires to each speaker directly from the head unit.
'88 ST-165(Black) - Sitting... Waiting... Quietly... in the garage under 2 inches of dust...
'88 ST-165(grey) - gone to rusty Celica heaven
'91 MKIII Supra - 98% completion!
Gold Member
Posts: 1682
Joined: Mon Aug 09, 2004 12:13 am
Location: Silver Spring, md

Postby beej » Mon Aug 09, 2004 1:37 am

save up and get an amp at the same time, that will power the 10 speaker system and over, so that wen u want to upgrade, u have the amount of power u need, and in the meantime whilst waiting, u can still use all 10 speakers......more money and werk, but i think that'd be the best option ;)
User avatar
Club Member
Posts: 741
Joined: Sun Aug 08, 2004 6:59 am
Location: Adelaide, Australia

Postby Gary » Mon Aug 09, 2004 3:03 am

You can run all speakers EXCEPT the door woofers using the builtin amp in your aftermarket head unit. There is a factory harness behind the place where stock head unit is located. You will need a Metra harness. to connect to that factory harness.

Then, you can run the door woofers using preamp output signal from your aftermarket head unit. You will need an external 2-channel amp. You will need to splice to the door woofer wiring under the passenger seat.

That's just one option to make all speakers work.
Other method will involve making your own wiring and/or run new speaker wires.

You can also opt for a sub box in the hatch instead of the door woofers.
I run the RCA cable from the head unit to carry the preamp signal to an external amp in the hatch. Then from the amp to the nearby sub box. The rest of the speakers are pushed by the builtin amp in the head unit.
93 ST185
GTFour God
Posts: 6430
Joined: Sun Aug 08, 2004 1:03 pm
Location: Carolina

Postby BoostedBlueToyotas » Mon Aug 09, 2004 11:59 pm

There was a huge thread on replacing the head unit and reusing
stock speakers and amp. It was a wiring kit you could get from
Circuit City ....

That thread really needs to be a sticky in this new forum :idea:
Tim Plessing
Columbia, MD

1990 ST185 - blue/blue cloth 152K-SOLD
1993 MR2 turbo - blue/black leather 59K TOTALLED/PARTING OUT
2006 Acura TSX - black/black 6 spd
2006 Mini Cooper S JCW Space blue/Silver roof 39k
2006 Mini Cooper JCW Silver/black roof 34k
Established Member
Posts: 2663
Joined: Mon Aug 09, 2004 11:33 pm
Location: Columbia, MD


Postby thkohlb » Tue Aug 10, 2004 4:30 am

or you could go crazy and buy my harness to my 92 system 10 and you can use the metra adapter for. also you can bypass the amp by simply unplugging the standard toyota plug behind the radio.
Tk 1992 Celica All Trac
Club Member
Posts: 213
Joined: Tue Aug 10, 2004 4:15 am
Location: Cincinnati

Postby SuperWhite92 » Tue Aug 17, 2004 12:23 am

Get Metra Harness 70-8112
Get Metra Pocket 88-00-8000
Plug and Play, baby
My 1992 Alltrac is for sale again.
User avatar
GTFour God
Posts: 3012
Joined: Sun Aug 08, 2004 3:29 pm
Location: Fort Collins, CO

Return to Audio / Wiring / Interior

Who is online

Users browsing this forum: No registered users and 1 guest