Dec 15, 2014, 01:10 PM
Last edit by: IB Advertising
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HOW-TO: SC300/SC400 Install Aftermarket Head Unit, OEM Speakers and Sub Working!
Ran into a snag on the subwoofer harness step. Everything else worked as described, including the step for hooking up the sub-out from the deck to the D1/D5 connectors. As expected, my setup has the subwoofer working only when the radio is on and the radio antenna is activated.
My problem is I got stuck on accessing the wiring harness, as described in step G. I got the rear seat and the package shelf off, but I couldn't seem to find a harness that looked like it belonged to the sub amp. The only harnesses I could locate were the two rear speaker and the subwoofer speaker harnesses. The amp itself didn't seem visible. Any suggestions?
Thanks in advance to anyone that can help out.
My problem is I got stuck on accessing the wiring harness, as described in step G. I got the rear seat and the package shelf off, but I couldn't seem to find a harness that looked like it belonged to the sub amp. The only harnesses I could locate were the two rear speaker and the subwoofer speaker harnesses. The amp itself didn't seem visible. Any suggestions?
Thanks in advance to anyone that can help out.
On my car the subwoofer amp is exactly where that silver cover is between the subwoofer and right side rear speaker.
What's underneath that if you look from the trunk?
What's underneath that if you look from the trunk?
I thought that might be it, but I couldn't verify, since my trunk subwoofer trim panel is still in place. I better go look for a thread that shows how to take off that panel.
the rear trunk panel is cake - it's all metal snap clips across the top edge only. just give it a good tug, one of the clips will pop out, then you can work the rest of the panel out.
Okay, now I'm stumped again. I pulled off the subwoofer panel (really easy like you said, BTW), but once I looked under there, I couldn't find anything that looked remotely like an amp. 
Last edited by FurySC400; Dec 29, 2010 at 01:33 AM.
I saw in a thread about the stereo in a 1992 SC that the amp might be on the right side of the trunk floor, so I lifted up the floor liner and saw something that I'm guessing is the subwoofer amp for a 1992 OEM Pioneer cassette playing deck. It's under that X-cage frame, taking up about 1/3 of the space inside the cage.
Here are a couple of pics of the wiring harness plug that goes into the "amp"(?). Would the wiring diagram in section "G" pertain to this harness as well? It looks like the wire colors shown in the diagram don't match my plug, but I'm wondering if the diagram colors aren't meant to be taken literally. Is the harness the same/similar, meaning, do I make the jumper splice the same way? 
Last edited by FurySC400; Dec 29, 2010 at 02:07 AM.
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Has anyone with the same setup (1992 SC400 w/Pioneer cassette and no CD-changer) been able to get the subwoofer to work during non-radio operation? Or even with non-radio use but with the antenna raised?
Otherwise, does anyone know if the setup I have shown in the pics above works with the diagram as shown under "Pioneer Sub Amp" from this link, even though I don't have a CD player. Andy would anyone know which wires to jump?
If my amp harness is different, does anyone have the correct wiring diagram for the harness leading into the amp on a 1992 SC w/out a CD changer?
Otherwise, does anyone know if the setup I have shown in the pics above works with the diagram as shown under "Pioneer Sub Amp" from this link, even though I don't have a CD player. Andy would anyone know which wires to jump?
If my amp harness is different, does anyone have the correct wiring diagram for the harness leading into the amp on a 1992 SC w/out a CD changer?
I have two questions, i used the metra harness the other day and got the whining sound and was just wondering if there is any way at all to fix it, ive looked it up and wherever i look it says its a grounding problem. tried grounding to the chassis directly and still got it. any help would be good.
And before this i did it your way but instead of cutting the wires by the amp i used a t-tap and my HU would shut off when i turned it up loud. do i need to cut is basically what im asking here?
And before this i did it your way but instead of cutting the wires by the amp i used a t-tap and my HU would shut off when i turned it up loud. do i need to cut is basically what im asking here?
Lexus Test Driver
Joined: Nov 2003
Posts: 814
Likes: 2
From: Tennessee
Ran into a snag on the subwoofer harness step. Everything else worked as described, including the step for hooking up the sub-out from the deck to the D1/D5 connectors. As expected, my setup has the subwoofer working only when the radio is on and the radio antenna is activated.
My problem is I got stuck on accessing the wiring harness, as described in step G. I got the rear seat and the package shelf off, but I couldn't seem to find a harness that looked like it belonged to the sub amp. The only harnesses I could locate were the two rear speaker and the subwoofer speaker harnesses. The amp itself didn't seem visible. Any suggestions?
Thanks in advance to anyone that can help out.
My problem is I got stuck on accessing the wiring harness, as described in step G. I got the rear seat and the package shelf off, but I couldn't seem to find a harness that looked like it belonged to the sub amp. The only harnesses I could locate were the two rear speaker and the subwoofer speaker harnesses. The amp itself didn't seem visible. Any suggestions?
Thanks in advance to anyone that can help out.
This might help click on the sub amp it gives you pinouts for both types of amps.
Has anyone with the same setup (1992 SC400 w/Pioneer cassette and no CD-changer) been able to get the subwoofer to work during non-radio operation? Or even with non-radio use but with the antenna raised?
Otherwise, does anyone know if the setup I have shown in the pics above works with the diagram as shown under "Pioneer Sub Amp" from this link, even though I don't have a CD player. Andy would anyone know which wires to jump?
If my amp harness is different, does anyone have the correct wiring diagram for the harness leading into the amp on a 1992 SC w/out a CD changer?
Otherwise, does anyone know if the setup I have shown in the pics above works with the diagram as shown under "Pioneer Sub Amp" from this link, even though I don't have a CD player. Andy would anyone know which wires to jump?
If my amp harness is different, does anyone have the correct wiring diagram for the harness leading into the amp on a 1992 SC w/out a CD changer?
Driver
Joined: Apr 2008
Posts: 154
Likes: 1
From: Oregon
I am about to do this and was wondering if any of the "Adapter harnesses" you can get, like through Crutchfield etc, will allow me to avoid all the seat pulling. THEY claim it is a splice/plug and go install as far as the wiring goes but after reading this thread I have my doubts.