You can absolutely use the stock speaker wire, it’s what I did with my aftermarket amp and it made my life much easier during the install.

The stock amp is located in the trunk, on the passenger side of the vehicle behind the trim. All you have to do is remove the wiring harness going to the amp (just clipped in) and splice in the new wires from the aftermarket amp into the existing harness.

My suggestion: the stock tweeters suck, and suck even more to get to. Luckily, the wires going to the tweeters and door speakers are separate in the stock harness. I would suggest buying ultra high quality coaxial speakers, like Focals or Morel Maximos, and putting them in the doors. That way you can bypass the stock tweeters altogether and still have great sound.

Wait, are you just installing a double din receiver and using the stock amp or are you installing an aftermarket amp as well?

If you are installing an aftermarket amp there is no need for the Beatsonic kit. (Edit for clarification: you will need it for the bracket, but you will not need any of the wires) If you are using the stock amp, I would just keep the stock tweeters and leave everything be

Just realized I didn’t really answer either of your questions.

Yes, that is correct, I just ignored the stock tweeter wires. And my car was non-nav, non ML so I just added an Alpine ILX207 head unit, an Alpine four channel amp, and a Rockford mono amp to power my JL W6 sub.

edit: Also, I used these Focal coaxials in the front doors

In stock form the crossover is located in the amp. So there are wires going to the woofers in the doors and wires going to the tweeters.

All you need are the wires going to the woofers in the doors. Your aftermarket amp will send a full range signal through those wires to your new coaxial speakers. The crossover on your speakers will then split the signal appropriately to the tweeter/woofer. No need to run any new wire.

It is true that you cannot eliminate your nav screen. You will simply be adding your carplay unit underneath. In order to do this you will need the Beatsonic bracket, however you will not need any of the wires that come with it. Those wires are used when people keep the stock amp. Essentially, the only wire you need is a power wire that turns on with accessory power to run the head unit.

Just found a pic of my 4 channel amp mid install. You can see there are 4 pairs of speaker wires leaving from it: one pair goes to each of the doors. Each of these pairs of wires was spliced into the appropriate wiring from the stock harness, which I unplugged from the stock amp.


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Thanks! The model I was looking at was a JL C5 Coaxial speaker. This model has a seperate crossover box outside of the speaker, and that has a place for woofer and tweeter wires. I am assuming I cannot use this model if I am using existing OEM speaker wire?

Since yours didn’t have these OEM Nav issues, I believe on my model, the OEM speaker wire plug I am unplugging, taking the wires out of the harness, and plugging them into my aftermarket amp?

That’s a good speaker too — love JL. You can still use those for sure — what you will do is run the wire from your aftermarket amp to the JL crossover (mount it somewhere in each door). Then, the JL crossover will have two outputs: one for the woofer and one for the tweeter. Wire them appropriately.

As for the nav/audio question: think of it this way — you are removing any semblance of the stock audio system on the car. Everything audio is going to be handled by your new head unit/ amplifier. The stock audio plug on your stock nav unit will not be needed. That is only needed for people that only want to add a new head unit but don’t want to go through the trouble of adding an aftermarket amp, like you’re doing.

I think we’re on the same page. I do not mean OEM head unit plug, I am talking about the OEM speaker wire plug that is plugged into the stock amp. I would have to remove that plug and take the speaker wire out of it if I want to utilize OEM Lexus speaker wire right?

Also, if I install crossover in the door, how can I use OEM tweeter speaker wire if I am not accessing the OEM tweeter? Wouldn’t I only have woofer wire? Sorry if I’m complicating the idea, thanks.

You will remove the wiring harness from the stock amp and cut off the plug. Identify the correct wire type that goes to each door woofer. Splice in new wire to these existing wires to your aftermarket amp. Ignore the stock tweeter wire.

The wire will will then go to your JL crossover. You will need to supply new wire that goes from the output of that crossover to the woofer and tweeter.

Yes that is exactly it. And yeah, 6.5 all around. You can get away with using a slightly cheaper speaker in the rear because ideally you just want the soundstage coming from in front of you and for the rears to just fill in sound