← Back to topic list

Unlocked speakers on 2020 M3 SR+

Kooter37 | 2026-02-13 01:19 | 65 views

I installed an aftermarket wiring harness that unlocked 6 additional speakers. I had no idea that Tesla installs all the speakers(minus subwoofer) from factory. I paid $35 for a wiring harness from Culmkari(Amazon) and it works great! The install took about 1.5 hours and was pretty straight forward. I watched a couple YouTube videos before and it went smoothly. I now have 14 functioning speakers. I plan on adding a sub at some point, but for now I’m happy. I highly recommend if you’re wanting to get more out of your stock setup!

Comments (36)
xxtremlockxx 2026-02-13 01:26

Rear tray speakers included?

gtech229 2026-02-13 01:27

Very nice. Been wanting to do that with my 2020 M3, do you have a link for the harness or videos you watched?

Kooter37 2026-02-13 01:29

Mine does have those. From what I can tell models produced before a certain date in 2020 had those installed. I was going to do it regardless, but it was a nice little bonus!

Kooter37 2026-02-13 01:32

https://preview.redd.it/8o8exsjk06jg1.jpeg?width=1320&format=pjpg&auto=webp&s=8bf21967c1202b4003055a87b0e6a52899aea71c This is what I got. I’d have to search for the YouTube videos. But I just looked up videos about installing the harness and a few popped up.

Kooter37 2026-02-13 01:34

The hardest part was getting it connected up under the glovebox. The rest wasn’t bad.

Buzzeh 2026-02-13 01:35

Does the gps voice work properly?

Kooter37 2026-02-13 01:50

Ooh, great question. I haven’t tried that since the install. I’ll give it a go tomorrow and report back.

Kooter37 2026-02-13 01:53

Update, I just tried it and it works fine.

joako537 2026-02-13 02:47

I have a 2021 sr+ do I have those speakers as well

Kooter37 2026-02-13 02:54

I think you have the ones at the top corner in the front and the ones by your front side windows in the corner, but I don’t believe you have the rear deck speakers under the back glass.

gtech229 2026-02-13 03:22

Awesome, thank you!

Blobwad 2026-02-13 03:30

Does it need to be an sr+ or can it just be a 2020 SR?

93Accord 2026-02-13 03:34

sick i heard about this long ago but never got around to it. will check when my car was made tmrw and see. sounds like 2020 sr+ made after march may not have rear deck speakers and i want those lol cars after october may require manual wire-tapping as plug-and-play connectors were removed (ai google search told me this)

corner 2026-02-13 03:36

But meaning to do this for a while but keep putting it off. Do you notice a meaningful difference?

Kooter37 2026-02-13 04:30

That sounds right. My car was originally purchased Dec. of ‘19.

cyyz2000 2026-02-13 04:31

Also curious

Kooter37 2026-02-13 04:31

You can tell for sure. But it makes me want a sub more now though.

Nicko971 2026-02-13 06:18

Yes you do, you’ll end up turning the treble down because the extra speakers sound so good at minimal adjustment, I believe you also hear more details for the high ends. If you have the rear parcel shelf speakers too then you get a more fuller sound from the back as well. Just beware some people say it makes the amp work harder as apparently the reason they are disabled is due to the lack of the rear amp for the subwoofer. This doesn’t make sense when you think about it as the plugs for them are at the front so wouldn’t make sense to run speaker wire all the way to the boot for surround sound speakers. But do keep that in mind if cranking and pushing speakers to their limits.

sciance7 2026-02-13 06:53

What videos did you watch?

Kooter37 2026-02-13 11:23

A guy named Travis M Thompson had a good one. I will say you should disconnect your negative battery terminal and the HV connector under the passenger backseat before messing with anything.

locksmack 2026-02-14 04:24

Now install the subwoofer. That made a way bigger difference than unlocking the extra speakers.

Kooter37 2026-02-14 04:53

Gotta have it.

Nazzrath 2026-02-14 05:02

Make sure you order the correct one for your car. There are a couple versions for different model years. In the kit I ordered, the cable to the rear speakers was not long enough even though it was the correct kit. Also, be careful you don't snag any wires under the B pillar or it'll cost you a visit to the service center.

kaimanson 2026-02-14 09:34

https://youtu.be/Vcfn22LvY6M My setup.

ayuzer 2026-02-14 17:12

On the contrary, I had to increase my bass to compensate for the increased treble from the re-activated tweeter speakers. The aftermarket wiring also has a crossover highpass filter included in line to further accentuate the treble In Those tweeter speakers. However, it definitely increases the sound room and resolution.

No1stopme1994 2026-02-14 21:20

I have a model 3 highland RWD LFP I’m pretty sure it’s marketed for 8 or 9 speakers will this work for my car

Kooter37 2026-02-14 22:59

Honestly I’m not up on all the models and what options they all have. I’d have to do some search to give you the correct answer. I know mine came with 8 working speakers and now I have 14. It gives much better all around sound now. It doesn’t help at all with bass as that only comes from the front door speakers. But it’s nice to have sound from all around now.

No1stopme1994 2026-02-15 00:55

Nice man! Still very smart regardless. If I had to guess my cars setup the same way. Not willing to pay 2-4K for speaker upgrade

perezidentially 2026-02-15 09:20

Nicely done! Do you feel fancy, though, is what I wanna know ? I love the chinese words. You'd think with ai, by now...this would be slightly better.

Rave-TZ 2026-02-15 13:26

I’ve considered this for my 2019 MR SR+

Kooter37 2026-02-15 13:30

It has a more complete surround sound now. But it made me want a sub more.

Lanky_Bobcat3075 2026-02-15 15:59

Didnt our sr+ 2019 come with premium audio?

Lanky_Bobcat3075 2026-02-15 16:00

I have the 2019 sr+ i thought these came with the premium audio already, how can i confirm for sure? It sounds great imo but not sure if im missing out

Kooter37 2026-02-15 16:22

You can put your ear up to the top corner tweeters or the surround speakers at the corner of your door next to the side mirrors. I’m pretty sure those are not activated from factory on any SR+ models. They are installed but not working. Also you should have the rear deck speakers under the back glass. I’m willing to bet those are not activated either.

Lanky_Bobcat3075 2026-02-15 16:26

I’ll test it rn, if thats the case I already know what im working on next weekend

Kooter37 2026-02-15 17:19

Good luck!

Add comment

Login is required to comment.

Login with Google