How-To aftermarket sound system info thread

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I know it's a long thread, but it is literally littered with best practices for tapping 12v sw. VCLeft is probably your best bet. See: this video.
I know i read through the thread and watched the video but that pin is taken by a RED (trailer) wire. I am thinking of the best place to reach and t-tap it if anyone can offer advice. I found it sort of goes to the rear of the car next to the high voltage wiring but not sure
 

R1Fast

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I know i read through the thread and watched the video but that pin is taken by a RED (trailer) wire. I am thinking of the best place to reach and t-tap it if anyone can offer advice. I found it sort of goes to the rear of the car next to the high voltage wiring but not sure
Ahh, I see. I didn't realize Telsa is populating that pin now. Ingineerix's videos should still be a good guide to navigate to and find/tap that same pin. That's how I'd go about it; just remove the lower trim and find the lead, then try to locate a good position in the wire to tap in.

If you'd rather try tapping it towards the rear and want to verify you've got the right wire (but lose track/can't visually verify every inch along the way, etc.) thats easy if you have a multimeter. Just Posi-tap that wire near the HV and test to make sure it's 13.8V while the car is powered on and ~0.0 V when fully asleep. If so its 99% likely the correct wire.

I would also recommend 16ga PosiTaps, not regular T-taps. PosiTaps do not budge and make a pin size hole in the jacket instead of a typical cut. They're more expensive but great quality: here's the best deal I found on Amazon (10 for $17)

Would it be bad to have 12V power from the penthouse go directly to the LC2i and have the Remote Out port of the LC2i trigger the relay when the audio system starts playing?
Yes. The relay has potential to cause back-current. If you use your LC2i to trigger it you run the risk of sending that current into the LC2i. You could run a ~1a fuse between the two but not ideal. Also your system will probably not fully shut off if you go this route (that's my guess anyway). If you've already tapped VCLeft just tap another line and fuse/run it to your relay.

I guess that's a long-winded way of asking if I still need to run a remote line to VC_LEFT?

Thanks!
You can provide 12v constant to all of your components from the penthouse, but you'll still want to tap VCLeft for remote turn-on. I know this will seem like plugging my own post (not meant to) but just use the left half of the diagram I attached as a guide and you won't go wrong. I've had it for 2+ months and it has been flawless. Not a single error message or issue.
 
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eXntrc

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The relay has potential to cause back-current.
I was under the impression that the back-current was from mechanical relays and I thought the diode was supposed to help with this?

I know this will seem like plugging my own post (not meant to) but just use the left half of the diagram I attached as a guide
Yes, I've bookmarked your diagram. And I planned to go that route for a long time. However, I ended up deciding to use a Solid State relay similar to what @_Travis_ did in part 9. My understanding is that the SSR won't have back-current and doesn't need the diode. So I was just trying to determine whether I should make things easier on myself.

But I have no problems routing the VC_LEFT. Especially since I've already tapped it and even added a breakout connector knowing I was going to do this work later. I will go ahead and use it for the relay.

My last question was what to use for remote-in. I was originally confused by this image from @_Travis_ in part 5 because it looked like he was tying 12V to remote-in after the relay:



I didn't know if that had something to do with delayed turn-on or trying to avoid any thump. But Travis did update that diagram in part 9 to this instead:



Which is more in line with what I would have expected, and this second diagram is what I will follow.

Thank you very much @R1Fast for documenting your install and for following up to answer my questions. I'm even buying some of the same parts you linked to, so everything you've posted has been helpful and appreciated.
 

R1Fast

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I was under the impression that the back-current was from mechanical relays and I thought the diode was supposed to help with this?... My understanding is that the SSR won't have back-current and doesn't need the diode.
It is, sorry I didn't look closelier to see you were going with an SSR. I believe those already have a diode/similar solution built-in but I personally would check to make sure that specific SSR you are using (either schematic or confirm w/manuf) to confirm before eliminating it.

My last question was what to use for remote-in. I was originally confused by this image from @_Travis_ in part 5 because it looked like he was tying 12V to remote-in after the relay: I didn't know if that had something to do with delayed turn-on or trying to avoid any thump. But Travis did update that diagram in part 9 to this instead
Yeah that threw me off as well as did a few diagrams/designs earlier in the thread from when Travis et al were initially figuring this stuff out. It didn't help that Tesla changed how VCLeft behaves when Sentry Mode was released, but luckily Power Off still shuts the system down and the car goes to sleep <15m with this setup even with Sentry Mode enabled. Anyway, the second diagram looks sound to me w/the exception of I would fuse every current carrying line at or below it's amperage capacity to be on the safe side.

Thank you very much @R1Fast for documenting your install and for following up to answer my questions. I'm even buying some of the same parts you linked to, so everything you've posted has been helpful and appreciated.
You bet! This $hit can be sketchy if you aren't a pro and the last thing any of us want is to brick our cars. :D
 

hamtonp

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I just came back to say that I've been running my amp power directly from the penthouse since end of March 2019. So about 5 months now. I haven't had and battery issues. I've been watching my battery voltage from my radar detector. The voltage is usually in the 12.8 - 14.3 range.
I guess I'm lucky.
 
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I did a tone test on the audio harness for the Model 3 SR+ delivered June 2019 and this is what I am using to do my install if anyone needs it.
Thanks for posting this. I am looking to tap the front dash speakers signal to power the a pillar tweeters at the bottom corner of the window.
Is it possible to add polarity to your diagram?
I’m also curious what you mean by “driver door woofer and tweeter”. Which tweeter are you referring to here?
 
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I did a tone test on the audio harness for the Model 3 SR+ delivered June 2019 and this is what I am using to do my install if anyone needs it.
Are all the signals full range? It is interesting that the front woofers would share signal with the tweeters. I figured the filtering would be done at the source.
 
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ATTENTION! SUPER IMPORTANT INFORMATION HERE!

LOL sorry for the outburst (And I'm not sure if this has been posted already) but I'm super stoked To get my stereo fully working finally ! Here is a major tip for anyone looking to do an after market install super easy, (stereo or otherwise perhaps, saw a few dash cam people) and get rid of those Pesky 12v needs service error.

It's such a stupid simple fix, but for those of you who don't know, i tried hooking up my 2000+ watt amps to the 12v, got error messages.... then tried hooking it up to the penthouse. EVEN with a resistor "trickle" relay it still tripped the e-fuse. and got 5+ more errors, couldn't even drive the car.

SO if you have a high powered system like I do (HD 1200 JL + mosconi component amp) whats the solution?

Keep it on the 12v but upgrade the battery. This thing saved my stereo, saved me from all kinds of headaches. No voltage sag. This thing kicks ass!

https://www.ohmmu.com/product-page/12v-lithium-battery-for-tesla-model-3

Your welcome! Spread the message!
 
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Just did some reading up on LC2i, it seems you'd want this device in your system as long as you are adding an amp to the factory setup. You'd want to put a LC2i between the factory hookup and the amp for your 8W3v3 so you can use the low level inputs. The high level inputs would carry the same attenuation from the factory system.
I’ve had good luck with high level inputs on different amps, but yes the quality will vary. Also, in my last install I tapped a subwoofer in my Audi A3 that has such a high output that it was clipping my amplifier. I decided to use a $30 outboard LOC. Gain was at minimum and when I listened to the system at a loud volume the LOC literally started smoking. The damn thing fried on me. That’s when I bought an LC2i. Works fine. I am definitely always going to use one of these, so the next thing to fry isn’t my factory sub amp. Ya know?!
 

eXntrc

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Keep it on the 12v but upgrade the battery. This thing saved my stereo, saved me from all kinds of headaches.
I have some questions:
  1. How frequently were you experiencing the power warnings before upgrading the battery?
  2. How long has it been since you upgraded the battery that you haven't seen the warnings?
I guess I'm trying to determine how sure you are that this is the solution to your problem and that the problem is solved indefinitely.

There are a number of lithium battery upgrades. One that has been quite popular on these forums is the EarthX:

https://teslaownersonline.com/threads/mpp-lightweight-lithium-battery-kit-now-in-stock.11049/

What lead you to go with the Ohmmu?
 
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I have some questions:
  1. How frequently were you experiencing the power warnings before upgrading the battery?
  2. How long has it been since you upgraded the battery that you haven't seen the warnings?
I guess I'm trying to determine how sure you are that this is the solution to your problem and that the problem is solved indefinitely.



There are a number of lithium battery upgrades. One that has been quite popular on these forums is the EarthX:

https://teslaownersonline.com/threads/mpp-lightweight-lithium-battery-kit-now-in-stock.11049/

What lead you to go with the Ohmmu?


1. Daily. After I kept taking it to La Jolla Audio (San Diego) We would try different things, every time.... Penthouse with resistor, 12v direct, 12v with resistor, etc... every time i would take it back to try something else the "Replace 12v battery soon" came on 4-6 hours after that. OR whenever the car was put to sleep and then woken up, whichever came first.

2. on Day 8 and I've been BLASTING the 2 JL 12s, I dn't normally listen to it that loud for long periods of time, but now i know, if I want to annoy / flex on the person mad dogging me at the red light with some 40 hz trap rap, i can!

Honestly, I found Ohmmu on youtube. I was just searching for batteries / solutions specifically aimed for aftermarket stereos. I messaged the dude (sounds like he works out of his garage in Arizona?) And he hooked me up with $50 bucks off.... So, I pulled the trigger.

For me, worth every penny. The "Penthouse" option didn't work for me. I kept tipping the "e-fuse" no matter what we tried. It was just a headache, and this just works. plain and simple.


Now we just have to figure out how to stop the UI car from displaying vehicles doing 360's moonwalks next to me when I'm parked at a red light. It's a bit embarrassing when you brag about your car being all cool, and then your friends get in and are like.... uhhhh, yeah bro whats up with the display? Those ares are spinning and crashing into each other...
 
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For this you would need to connect to a turn-on signal, such as the trailer supply in VC_LEFT. There's no way to do signal turn-on with the relay. It's not very difficult to do though, just requires a plastic prybar, 20 feet of wire, and a 0.25" quick disconnect.


So terminals 1&2 are power and 3&4 are control. Terminal 2 goes to P12V, terminal 1 goes to the stereo equipment, 3 goes to your turn-on signal, presumably the pin on VC_LEFT, and terminal 4 goes to ground. That will isolate your entire stereo completely from the car when the car is shutdown and connect it when the car is running.
Does it make any sense to use a relay in conjunction with the LC2i?

Edit: I found the answer later on in the thread. @RoccoX clarified that you want to use a solid state relay to avoid back current into the LC2i (as per @eXntrc ).
This all leads me to a different question, what happened to the 12 vote automotive relay that @Jamie Sibley pioneered? More people are taking about the pac-80. Can the fly back diode be used with the basic auto relay shown above? (already have one)
 
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eXntrc

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We would try different things, every time.... Penthouse with resistor, 12v direct, 12v with resistor, etc... every time i would take it back to try something else the "Replace 12v battery soon" came on 4-6 hours after that. OR whenever the car was put to sleep and then woken up, whichever came first.
Thanks for the info. I'm just curious though, what relay did you use? Was it a Solid State? Was it the PAC-80? Also, what did you use for the trigger side of the relay? Did you trigger that from VC_LEFT or something else?

The point of triggering the relay from VC_LEFT is that VC_LEFT turns on a few seconds after the penthouse. To blatantly steal from @_Travis_ :


So after the penthouse turns on but before VC_LEFT turns on, the amplifier is 'bleeding' voltage through the 2.4 ohm resistor. A few seconds later VC_LEFT kicks in and the amplifier is then connected directly to the penthouse.

I'm wondering if there was some kind of timing issue for you. For example, some have suggested triggering the relay from the LC2i remote out and having it use GTO. But if the LC2i was to turn GTO on as soon as the penthouse comes on, there would be no delay.

I found Ohmmu on youtube. I was just searching for batteries / solutions specifically aimed for aftermarket stereos.
I spent a lot of time researching Lithium Batteries yesterday after your post. I searched the forums here. I searched Ohmmu ratings on Amazon. I searched YouTube videos. There just seems to be so little first-hand feedback from users who have made the switch to Lithium. Especially over the long term. Some people claim the Lithium life span is much shorter in harsh climates. Yet those YouTube videos you saw and Ohmmus own website claim they do a bunch of testing at harsh temperatures and they should outlast lead acid. I just can't find any definitive source that I trust.

At this point, I guess I just haven't seen enough supporting evidence to spend the $450 plus on that battery. But if I do end up hitting any power issues, it will probably be the first thing I purchase.
 

eXntrc

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Can the fly back diode be used with the basic auto relay shown above? (already have one)
That relay you showed is only rated to 40A max. 1,000 watt amplifiers generally pull up to 100A peak. You'll want to make sure your amplifier would never exceed the rating of the relay.

In my experience so far... my suggestion would be to not skimp on this part. Go with the PAC-80 and diode or go with a high quality Solid State relay.

I tried this one and I do NOT recommend it:


@_Travis_, @R1Fast, @Jamie Sibley, @RoccoX have any of you thought about what will happen to the resistor in case of relay failure? Will it just burn out and you're OK with that, or should there be another fail-safe here?

I will do a full write up of my system when it's done, but even though the relay above is rated for up to 120A it did not behave correctly. With no load or even a light load, the relay seemed to work. 0 volts when off, 13.8 volts when on. But once I connected the JL 1200/1 amplifier the relay started behaving very strangely. 0 volts when off, 0.037 volts when on (when the resistor was out of the circuit). Because the relay wasn't doing its job, all of the amplifier load was being passed through the resistor. Which obviously got very hot very quickly. Needless to say, I ripped that relay out of the system and proceeded to buy the D06D100 that Travis used.

Now, this could have just been really bad luck. Maybe I got a bad relay. But everyone, be sure to test your relay under load. Be sure to monitor the temperature of the resistor. It's normal for it to get warm during the few seconds between the penthouse turning on and VC_LEFT turning on. But it shouldn't continue to heat up beyond that. I just worry about what might happen in the future if the relay fails and the resistor goes into thermal runaway.
 
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That relay you showed is only rated to 40A max. 1,000 watt amplifiers generally pull up to 100A peak. You'll want to make sure your amplifier would never exceed the rating of the relay.

In my experience so far... my suggestion would be to not skimp on this part. Go with the PAC-80 and diode or go with a high quality Solid State relay.

I tried this one and I do NOT recommend it:


@_Travis_, @R1Fast, @Jamie Sibley, @RoccoX have any of you thought about what will happen to the resistor in case of relay failure? Will it just burn out and you're OK with that, or should there be another fail-safe here?.
I will be using 1 mono block class D (500W peak) powering an eBay stock sub for fill. It’s super compact like the alpine ktp-445, and using conjecture assume that the caps aren’t too big. Like @PLUR I could use no relay at all, but I want something. I can never be late for work! But I get what you are saying, the regular auto relays are rated too low of an amperage and generally going to be too low for what these other guys are running (6 channels and stuff)

Also, I though the advice was to add a 5A fuse to the resistor that feeds the relay, blowing out in case of relay failure.
 

eXntrc

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I can never be late for work!
I hear ya! Necessary or not, you have the peace of mind.

I though the advice was to add a 5A fuse to the resistor that feeds the relay, blowing out in case of relay failure.
Oh, if that advice had been given I guess I missed it. I'm confused how that would work though. Would it be a slow-blow fuse or something? Every time the car starts the penthouse will come on for a few seconds before the relay does. I would imagine that a fuse would blow during that time, would it not?