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12v Switched?

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My english is not that great and have a bit hard to keep up what you talk about.
Is VCright the way to go with a relay to get the swiched? And is it still swiched after the 2020.20 update?
The red wire from VCRight turns on after you press the brake pedal for the first time and off when you get out of the seat. The center console led switch circuit turns on when you open the door and turns off when you leave the car and close the door. Both are working with the 2020.20 update, you can choose which works best for you.
 
Im still pulling power off VCLeft using a relay off the console light and agree that its seems weird using that for trigger but i think part of that was prior people using the console light like a switch

I got tired of waiting for a better fix and my son offered to help me yesterday, so we did this brown wire hack as well. We used this ASH-100DD solid state relay that I got on Amazon for $12 bucks and it worked great.

M3S-Power-Relay.jpg

  • Bottom-Left: Ground
  • Bottom-Right: Brown wire from center console
  • Top-Right: Blue accessory wire or VC_LEFT
  • Top-Left: Your equipment
Now your equipment will turn on when you open the door and turn off when you get out and close the door, like before 16.2.1.

the brown wire is basically accessory power.

Yes, but with the very important difference that it switches based on whether the door is open or the vehicle is occupied. Thank you @Idkorcare for finding this.

Just toss a 1 amp fuse on it if you are worried about it messing with something.

This really shouldn't be necessary. You may trip the e-fuse, but it should reset when the car goes into deep sleep. Or you can reset it immediately with a hard reset.

for your #3 problem how are you triggering the amp relay/solenoid and turning your amps on?

I never did use the GTO. Right now my amps turn on when the door opens. This always worked for me before and is still working for me now. If I have problems going forward, I can switch to using GTO.

The brown center console led switch circuit wire can be accessed in the VCLEFT footwell area. It’s a thin gauge brown wire in a large bundle. There is identical brown wire in the bundle so you’ll need to use a multimeter to test.

Oh man. If I'd known this before yesterday it could have saved me running a wire to the center console. But there are so many wires in that bundle and they're pretty thin. I get nervous pulling that bundle apart and splicing into things just to test I have the right wire. I wish there was an easier way to identify them. But thank you for sharing @todd2fst4u. Hopefully that will save someone else having to run the wire.

you can get 12 V accessory source from the ODB2 plug (Pin 4 & 5 Ground, Pin 16 Power + 12 V)

From what I've read, it's been verified that the ODB2 accessory line stays powered until the vehicle goes to sleep. While this may be what the OP asked for, people later in this thread have been searching for more of an "occupancy aware" accessory line. The car can take many hours to go to sleep. Many times mine doesn't sleep until around 1 AM, and I don't want my amplifier, radar detector, etc. left on that whole time. The brown wire we've been discussing above is only powered when someone is entering or actually in the car, which is ideal for these kinds of accessories.
 
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The red wire from VCRight turns on after you press the brake pedal for the first time and off when you get out of the seat. The center console led switch circuit turns on when you open the door and turns off when you leave the car and close the door. Both are working with the 2020.20 update, you can choose which works best for you.

This is new to me. Have you verified this yourself @todd2fst4u or did you read it somewhere? If you read it somewhere, could you share a link?

I ask because I thought @Ingineer said that red wire at VCRight is the same red wire that goes into the amplifier in the trunk. I have personally verified that after 16.2.1 the red wire at the amplifier in the trunk does NOT turn off when you exit the car. The stock amplifier in my trunk remains powered until the vehicle sleeps.

If indeed the red wire in VCRight is not the one going to the amp in the trunk, this would be good to know.
 
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If there is no audio signal, then the audio amplifier should not consume too much energy?

Unfortunately this is not always correct, depending on your equipment. As I mentioned in post #70, my HD1200/1 amp has reached 125 F just sitting in the trunk without anything playing. And I've noticed much more vampire drain since 16.2.1.

My car can go many hours without sleeping, especially while charging. Having my amp baking at 125 F in the trunk that whole time makes me very nervous. I'd much rather it cut off the moment I get out of the car.

As @todd2fst4u has pointed out, I could use the GTO (audio sense) trigger to turn the amp on and off. However, that would still leave my radar detector and laser module on, and the laser module generates quite a bit of heat too. For me it's just much better if all the accessories shut off when I exit the car. For someone who only has a radar detector or dashcam and they're OK with it staying on for potentially hours without occupancy, the regular accessory line is fine.
 
This is new to me. Have you verified this yourself @todd2fst4u or did you read it somewhere? If you read it somewhere, could you share a link?

I ask because I thought @Ingineer said that red wire at VCRight is the same red wire that goes into the amplifier in the trunk. I have personally verified that after 16.2.1 the red wire at the amplifier in the trunk does NOT turn off when you exit the car. The stock amplifier in my trunk remains powered until the vehicle sleeps.

If indeed the red wire in VCRight is not the one going to the amp in the trunk, this would be good to know.
Yes I have verified this myself. I’m using the red wire on VCright shown in this video to trigger a relay for my radar detector. I can’t confirm this is the same wire @Ingineer mentioned however because I have a SR+, no oem amplifier in the trunk.
 
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@eXntrc glad you got it working, i tossed out the fuse idea just to make you feel better about grabbing that wire but we cant really check what all is already fused and it current rating.

Ive never been a fan of signal sensing turn ons but thats from being in car audio when it feels like it first came out that I remember, around 2000, and it didn't work all that great. Now and especially with the AudioControl devices it seems to work great. Im using a JL RD500/1 and JL RD400/4 so not quite as much current draw but but did get a warning once when i had everything turning on differently.

i have not noticed significant heat off my amps yet , next drive ill check and see how warm they get.

Where did you ground the amps at and how is you gain adjusted on the amp and LC2i?
 
Not sure what the norms are for cross-posting, but I just asked on this new thread whether switched 12V power could be retrofitted via an after-market OBD adapter for pre-May 2020 Model 3s:

May 2020+ Model 3 have J1962 (OBD-2 style) connector for third-parties (including 12V)

thats basically the same thing watts_up was showing eariler in the thread and its most likely just grabbing power off the blue power outlet wire which works the same as VC_Left does after the update.
 
thats basically the same thing watts_up was showing eariler in the thread and its most likely just grabbing power off the blue power outlet wire which works the same as VC_Left does after the update.

Aghhh. Sorry! I had seen that earlier, but for some reason thought it was from another post, couldn't find it and then forgot that it--and the answer!!--was just above my dumb question when I posted.

A heads-up for folks with the new OBD-2 port...my installer makes a great point when he says that service techs don't like seeing things hooked up (or, better yet, soldered) to those ports, and can cause you grief if you have to take it in. Just a passing comment that I thought I'd, in turn, pass along to at least try to offer something up besides a mea culpa!
 
Yes I have verified this myself. I’m using the red wire on VCright shown in this video to trigger a relay for my radar detector. I can’t confirm this is the same wire @Ingineer mentioned however because I have a SR+, no oem amplifier in the trunk.

Verrrrry interesting. I wonder if that's actually a different wire or if it's a different behavior between the SR+ and Premium Sound. Mine is working great for now, but I'll keep this wire in mind in case I need to find another option later.

Where did you ground the amps at and how is you gain adjusted on the amp and LC2i?

I cover the ground in Part 3 of my blog series covering my install and I cover the LC2i settings in Part 7. In Part 7 look for "Connecting the Audio", but note that I also did a DSP to calibrate it specifically with the stock audio system (and remove the 50 Hz bump). That same article includes my DSP files if you would like to use them too, though the DSP file matches the premium sound system. I have another article in that series that covers doing your own calibration if you don't have the premium sound.
 
Yes I have verified this myself. I’m using the red wire on VCright shown in this video to trigger a relay for my radar detector. I can’t confirm this is the same wire @Ingineer mentioned however because I have a SR+, no oem amplifier in the trunk.
The video recommends hooking up to a relay and tap the 12V battery for main power source, but if I don't want to do that, am I correct in my understanding that I can just tap this red wire and connect the other end to any ground (like a nearby bolt) for the switched 12V power?
 
Verrrrry interesting. I wonder if that's actually a different wire or if it's a different behavior between the SR+ and Premium Sound. Mine is working great for now, but I'll keep this wire in mind in case I need to find another option later.



I cover the ground in Part 3 of my blog series covering my install and I cover the LC2i settings in Part 7. In Part 7 look for "Connecting the Audio", but note that I also did a DSP to calibrate it specifically with the stock audio system (and remove the 50 Hz bump). That same article includes my DSP files if you would like to use them too, though the DSP file matches the premium sound system. I have another article in that series that covers doing your own calibration if you don't have the premium sound.

OK so first off I dont know what you know and I have an SR+ but ill make a couple suggestions.

1. You want your ground as short as possible. It looks like you grounded it to that thin metal that comes off the taillight. I grounded mine the the brace that runs between the wheels, sanded it down to bare metal then used 3 self tapping screws. Its more solid and thicker metal. The brace under the wood. Your ground will work its not a good one. If you can use a bolt there even better, ive never had an issue with just self tapping screws. If anything I would just try something more solid.
M3S-Power-Trickle01-1024x768.jpg


2. this one might be a little more tricky with your set up but you want to get the amp input sensitivity as low as possible buy making the DSP and LC2I doing more of the work. i didnt see the max input input/output for the mini DSP on amazon and i think your amps max input input/output is different that mine but if you can you want to turn up the bass knob on the LC2I and turn down the amp gain. I cant tell from the pic how high the amp sensitivity is but it looks at least halfway up.

I went for a drive yesterday for about 45 min with the stereo cranked for a good portion of that and when I got home my amps were warm at best and im using lower line JL amps with no airflow in the subtrunk. I have my LC7I turned up 95% of the way and the gain on the amp around 10-25% at most but I did have to change the input voltage to high otherwise it was to much and send the amp into protection when turned up. I also used an Epicenter instead of a DSP to correct the sub levels
 
Hey Audio Gurus,

I've been creeping this thread for a while now as I'm having the same issue since the latest update. My current setup has the remote wire tapped into VCLeft but I'm going to try and look for that thin brown wire this weekend. If my understanding is correct, it's bundled in that main harness at VCLeft where that thicker red wire is located...correct?

Secondly, where is everyone drawing power from? When my system got installed by local professionals, they tapped into the 12v battery up front. From what I've read on other forums, it seems like the 12v battery isn't a very good source for power as 1) it's monitored by the car and will throw a warning if there's too many discharge/charge cycles = end of life and requires service & 2) the lead acid battery is way under sized for a sound system. My 12V was literally replaced a few days ago after a warning so I wanna make sure moving forward I don't run into the same issues. During my warranty battery replacement, the mobile service tech was asking if I had any aftermarket parts on my car in which I said not currently (I had hidden my power wire so it wasn't visible).

Any help would be greatly appreciated.
 
Hey Audio Gurus,

I've been creeping this thread for a while now as I'm having the same issue since the latest update. My current setup has the remote wire tapped into VCLeft but I'm going to try and look for that thin brown wire this weekend. If my understanding is correct, it's bundled in that main harness at VCLeft where that thicker red wire is located...correct?

Secondly, where is everyone drawing power from? When my system got installed by local professionals, they tapped into the 12v battery up front. From what I've read on other forums, it seems like the 12v battery isn't a very good source for power as 1) it's monitored by the car and will throw a warning if there's too many discharge/charge cycles = end of life and requires service & 2) the lead acid battery is way under sized for a sound system. My 12V was literally replaced a few days ago after a warning so I wanna make sure moving forward I don't run into the same issues. During my warranty battery replacement, the mobile service tech was asking if I had any aftermarket parts on my car in which I said not currently (I had hidden my power wire so it wasn't visible).

Any help would be greatly appreciated.
You are correct, the thin brown wire is bundled in the same area as the red wire you are using now. There are 2 thin brown wires in this area. You’ll need to use a multimeter to test which is the correct one. The correct one will have 12v when the car is on, and turns off immediately when you leave the car and close the door.

It is recommended to pull power for your amp from the penthouse 12v connection located under the passenger side rear seat.
 
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You are correct, the thin brown wire is bundled in the same area as the red wire you are using now. There are 2 thin brown wires in this area. You’ll need to use a multimeter to test which is the correct one. The correct one will have 12v when the car is on, and turns off immediately when you leave the car and close the door.

It is recommended to pull power for your amp from the penthouse 12v connection located under the passenger side rear seat.
Thanks for your quick response @todd2fst4u, I brought this to my installer's attention but they seem to think the 12v battery up front would provide a battery "reserve" for the amps. I just hope I don't have to replace the 12v again or else Tesla's gonna think something is fishy. My car is almost 1 years old with ~8500kms
 
Thanks for your quick response @todd2fst4u, I brought this to my installer's attention but they seem to think the 12v battery up front would provide a battery "reserve" for the amps. I just hope I don't have to replace the 12v again or else Tesla's gonna think something is fishy. My car is almost 1 years old with ~8500kms

i wired a simple voltage meter to the 12v battery to see what was going on and ran my amps straight off of it. At a certain point the load on the battery was more than the car liked and it stopped charging the 12v battery and voltage would just start to drop. Once the 12v battery drops below a certain level(<12v?) it will toss a warning that the battery is bad and will not attempt to charge it until its back over the min level and the car is reset.

I didnt push it to hard when it did that but if i turned the music down it would start to charge again so no idea what would have happened if i didnt see that it was doing that.

I dont like running straight off the penthouse but it works just fine
 
i wired a simple voltage meter to the 12v battery to see what was going on and ran my amps straight off of it. At a certain point the load on the battery was more than the car liked and it stopped charging the 12v battery and voltage would just start to drop. Once the 12v battery drops below a certain level(<12v?) it will toss a warning that the battery is bad and will not attempt to charge it until its back over the min level and the car is reset.

I didnt push it to hard when it did that but if i turned the music down it would start to charge again so no idea what would have happened if i didnt see that it was doing that.

I dont like running straight off the penthouse but it works just fine
Thank you for that information as well @Idkorcare , maybe I'll have to forward these findings to my installer and maybe i'll be the guinea pig and see what happens. I'm also planning on eliminating the remote wire completely and using the signal from the headunit to turn on the amps. I'm afraid the properties of the brown wire might change in the future and we'll be back to square one...maybe i'll just get this all done at once and see how it goes
 
Thank you for that information as well @Idkorcare , maybe I'll have to forward these findings to my installer and maybe i'll be the guinea pig and see what happens. I'm also planning on eliminating the remote wire completely and using the signal from the headunit to turn on the amps. I'm afraid the properties of the brown wire might change in the future and we'll be back to square one...maybe i'll just get this all done at once and see how it goes

Power off the DC-DC you will most likely have to use the relay/resistor setup to prevent it surging the DC-DC at turn on and causing errors. Signal sense also stays on longer than you will probably want like during sentry or battery conditioning, even tho there is no sound the car is still awake and it keeps the signal sense on, or at least in my case it seemed no better than the new VC_Left change
 
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Power off the DC-DC you will most likely have to use the relay/resistor setup to prevent it surging the DC-DC at turn on and causing errors. Signal sense also stays on longer than you will probably want like during sentry or battery conditioning, even tho there is no sound the car is still awake and it keeps the signal sense on, or at least in my case it seemed no better than the new VC_Left change
You make a very good point about the signal sense. Maybe I'll tap into the brown wire and relay power from the thicker red wire.

I'm also running Audison Prima amplifiers and they have delay turn-on which is adjustable in the settings which is a nice feature.
 
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