LC450 Radio amp bypass help needed (1 Viewer)

This site may earn a commission from merchant affiliate
links, including eBay, Amazon, Skimlinks, and others.

Joined
Apr 13, 2010
Threads
12
Messages
97
i am having issues with my radio - the PO installed an Alpine 9830 HU and installed Boston Acoustic woofer and tweets in the front (6.5 woofers in doors and tweeters in bottom of dash). My right side speakers in the front are very distorted. I tried hooking up a brand new speaker but they are also distorted.

The PO ran the system thru the factory amp from what i can tell. I am hoping the factory amp is bad and i want to bypass it. I am very confused after reading several dozen threads of more.

I am not sure anyone used an adaptor to plug the aftermarket HU in. IT looks like they cut up the factory one? See picture.

Can someone walk me thru with decent detail how i can still bypass the factory amp? It looks like they wired the preamps coming out to the existing wiring. HELP! THx

FullSizeRender.jpg
 
All you should have to do is unplug the pre outs (the four RCA style cables) and route them to your new amp. Then run new speaker wires to your speakers. If you want to use existing factory wiring, it's going to be a bit more complicated. It does look like your factory harness was cut. Why do people do that? A metra harness adapter is $12.
 
your apline probably has more power then the lx amp anyways. Go to best buy buy this adapter Metras 70-1761 add about 24 inches of wire ,find the printout for the alpine wiring it should have a big plug that doesn't use the rca outlets the apline plug will go into the radio the Metras will plug in over on the right side of your glove compartment where the existing amp is plug in. now you have bypassed the amp and our now using the radios amp threw the factory wiring.
 
sorry gave you the wrong adapter number it has been corrected in the post
 
i am sl;lightly confused - will i connect to both of the plugs i see running into the amp by the glovebox or just one?

your apline probably has more power then the lx amp anyways. Go to best buy buy this adapter Metras 70-1761 add about 24 inches of wire ,find the printout for the alpine wiring it should have a big plug that doesn't use the rca outlets the apline plug will go into the radio the Metras will plug in over on the right side of your glove compartment where the existing amp is plug in. now you have bypassed the amp and our now using the radios amp threw the factory wiring.
 
the metra convector will connect to the alpines factory plug radio may have the pin out for the wire loom on the radio.in between those connectors factory and the metra you will add two foot of wire .apline will connect to the radio and metra end will connect to the lx wire loom by the radio alpine #---------------------- metra-. lx wire loom connector by factory amp
 
let me see if i understand. You bought the toyota adaptor and then added a couple feet of wire. Both plugs from the amp connect to this new wiring harness and then u connect it to the wires coming out of the new head unit? will this also work for mine considering it looks like my factory radio plug is all cut up?

thx for your help! i must be slow at understanding this!


 
I must be slow as i do not fully understand your instructions - i am going to buy a metro connector ......... add 2 feet of wire to it ......... on one end i am plugging into the existing connections by the amp? Correct? and then the other end i am going to connect to my new HU? keep in mind that someone already cut up the factory plug from the original HU.

let me know what you think hen u get a chance! thx a ton for the help.


the metra convector will connect to the alpines factory plug radio may have the pin out for the wire loom on the radio.in between those connectors factory and the metra you will add two foot of wire .apline will connect to the radio and metra end will connect to the lx wire loom by the radio alpine #---------------------- metra-. lx wire loom connector by factory amp
 
That's correct, here is a link with a picture of the said wire extension,
1997 LX450 Stereo /Power antenna /Amp bypass 1997 LX450 Stereo /Power antenna /Amp bypass



Basically you
1. take out the amp
2. splice the metro harness together with 20-24 inches of wire to your stereo harness, I did it one wire/color at time. Start with your radio harness side because metro harness has more wires than you might need.
3. Connect metro plugs to factory plugs by the amp.(I would throw away the amp)
4. Run the harness behind the glove box and it goes right into the area behind the stereo and plug it in.(tape the wires together)
5. Enjoy the test tunes with a cold one.

Once you figure it out its quite easy.

While you are in there might as well run the rca and power cable for an amp for sub.
 
thx u so much! how do i deal with the fact my factory harness at the rear of the radio was cut so they could wire the latest head unit to it? would i just connect wire to wire from the existing bundle of wires?

also maybe u can shed some light on the amp? i see 2 plugs going into the amp? and i am not sure if there are other plugs or wiring going into it or out of it? so i am slightly confused as to how i can pull both plugs out of the amp and have them power the various door speakers?




That's correct, here is a link with a picture of the said wire extension,
1997 LX450 Stereo /Power antenna /Amp bypass 1997 LX450 Stereo /Power antenna /Amp bypass



Basically you
1. take out the amp
2. splice the metro harness together with 20-24 inches of wire to your stereo harness, I did it one wire/color at time. Start with your radio harness side because metro harness has more wires than you might need.
3. Connect metro plugs to factory plugs by the amp.(I would throw away the amp)
4. Run the harness behind the glove box and it goes right into the area behind the stereo and plug it in.(tape the wires together)
5. Enjoy the test tunes with a cold one.

Once you figure it out its quite easy.

While you are in there might as well run the rca and power cable for an amp for sub.
 
thx u so much! how do i deal with the fact my factory harness at the rear of the radio was cut so they could wire the latest head unit to it? would i just connect wire to wire from the existing bundle of wires?

also maybe u can shed some light on the amp? i see 2 plugs going into the amp? and i am not sure if there are other plugs or wiring going into it or out of it? so i am slightly confused as to how i can pull both plugs out of the amp and have them power the various door speakers?

Once you unplug the factory stereo and decided to bypass the amp then simply tuck the factory harness away and forget about it!

There are 2 plugs and the new metra harness will also have 2 plugs for them.....match up the color of wire to your stereo harness and you are done! Those wires go to your speakers and your head unit has built in amp that will power the speakers.
 

Users who are viewing this thread

Back
Top Bottom