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Wait, what? Links, photos, discussion????
I will do a full writeup once I have everything working, but here is a teaser image...

On the right side is a model 3 SCCM disassembled into its components. The stalks are modular and can be removed.

On the left is the plaid SCCM. The housing is identical to the Model 3. :) The turn stalks snap right into place on the Plaid housing.

Unfortunately (but not unexpectedly), the Plaid sccm doesn't send CAN messages for the stalks, so I am adapting things to work. It involves some CAN message translation for now. Eventually I'll probably figure out how to make a small module to talk to the stalk ribbon connectors directly.

Edit/note: Also yes there are connectors for the stalk ribbon cables on the Plaid SCCM, but they are non functional, likely just a firmware difference. It means you cannot simply pop the stalks into the Plaid SCCM and plug in the ribbons to make things work.

IMG_4043.jpg
 
There is definitely an OBDII port in the refreshed (2021) Model S. Got connected to it and there is a 12 v pin there. However, it’s not switched power.

Also, checked the Tesla diagnostic port above the wireless charging pad and the best I can tell it is not switched power either. Still have power there with the car turned off. I’m using pin 20 for ground and pin 1 for the 12v. Maybe @rhuber can confirm?

I‘m trying to figure the best way to get power to a radar detector and want to make sure it’s switched power to avoid unnecessary battery drain.

Thanks. Brian

Can you (or anyone) confirm which can busses are present on the refresh OBD port? It would be nice to be able to confidently tell folks they could connect an OBD dongle or canserver there without the need for any 3rd party harness.
(I would guess/hope vehicle bus is present, but diagnostic connector is needed for access to multiple busses)
Is it located in the footwell or the center console?
I sure wish we had wiring diagrams!
 
Can you (or anyone) confirm which can busses are present on the refresh OBD port? It would be nice to be able to confidently tell folks they could connect an OBD dongle or canserver there without the need for any 3rd party harness.
(I would guess/hope vehicle bus is present, but diagnostic connector is needed for access to multiple busses)
Is it located in the footwell or the center console?
I sure wish we had wiring diagrams!
I can't answer most of the questions for you, but can tell you that it appears to be in the same location as prior MS's, in the top left of the driver's footwell.
 
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There is definitely an OBDII port in the refreshed (2021) Model S. Got connected to it and there is a 12 v pin there. However, it’s not switched power.

Also, checked the Tesla diagnostic port above the wireless charging pad and the best I can tell it is not switched power either. Still have power there with the car turned off. I’m using pin 20 for ground and pin 1 for the 12v. Maybe @rhuber can confirm?
I'm pretty sure the Tesla drag port above the wireless pad is switched, as my CANserver is hooked up to it and goes offline once in a while - and it seems to correlate to when the car is asleep, unless @JWardell has some kind of timer to let CANserver sleep after some period of inactivity? Doubtful as I wouldn't know how to "wake" it up again if it did..
 
I'm pretty sure the Tesla drag port above the wireless pad is switched, as my CANserver is hooked up to it and goes offline once in a while - and it seems to correlate to when the car is asleep, unless @JWardell has some kind of timer to let CANserver sleep after some period of inactivity? Doubtful as I wouldn't know how to "wake" it up again if it did..

AFAIK the diag connector 12v is switched on recent S/X but always on for older cars (and no 12v in '21 3/Y)
 
I zoomed in and straightened your photo. Can you please tell me which is 12v and which is ground?
View attachment 711326

Also, I searched around for a matching connector without success. I did find this, though I have zero clue of the size and whether it would come close to fitting:
4 Pin Female Connecor
View attachment 711325
Based on your edited picture.
Top Left - Ground, Black wire
Bottom Left - 12V, Red wire
If, and BIG IF, it’s the trailer ECU connector then the other two on the right side are trailer related (Brake switch and trailer brake).

That being said, I picked up a Model X trailer brake ECU adapter (1072586-00-A) from Tesla today and it fits the connector. Only Cost $4.40.

My take is that Tesla has common parts and configurations that are shared among different models as a cost savings measure which is why that connector is in the refreshed Model S. The good news for me is that I can get switched 12v that is off even when sentry mode is on.
 

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I'm pretty sure the Tesla drag port above the wireless pad is switched, as my CANserver is hooked up to it and goes offline once in a while - and it seems to correlate to when the car is asleep, unless @JWardell has some kind of timer to let CANserver sleep after some period of inactivity? Doubtful as I wouldn't know how to "wake" it up again if it did..
I noticed was that the power switched off when the car went to sleep but if I set the alarm with sentry on then there was power on pin 1. Not saying that’s the absolute final answer - just what I think I was seeing in my limited testing.
 
I noticed was that the power switched off when the car went to sleep but if I set the alarm with sentry on then there was power on pin 1. Not saying that’s the absolute final answer - just what I think I was seeing in my limited testing.
Oh yeah, turning on Sentry mode will definitely prevent the car from sleeping, so there will most likely still be power to the diag port.

If you let the car sleep though (turn off Sentry and other API pings such as Tesla app or 3rd-party sites), power to the diag port should drop.
 
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Hey, so the turn signal stalk is all wired up and works! It I also have wiper control button working exactly as it does on the 3/Y, and flashing brights by pulling back on the stalk works as well. I rarely used the pushing forward motion in my 3 to enable/disable automatic brights, so instead I actually made that into a Homelink trigger, and it is absolutely awesome.

I'll need time to get it written up, and there is some basic soldering involved. I'm using a Particle Photon + Carloop to read the state of the stalk and send CAN messages to the car, so nothing stock is modified and the change is entirely reversible. I'll create a git repo with the instructions to recreate the work and a BoM.

Note: I have zero interest in selling or supporting this, so it will be an entirely DIY endeavor if folks want to do it. However, I do expect that approx 3 days after I publish the info, you'll be able to buy one on alibaba.

This is an UNLISTED youtube link, so please don't share beyond the forum for now. I am planning to do a better quality video about the project soon.

 
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Hey, so the turn signal stalk is all wired up and works! It I also have wiper control button working exactly as it does on the 3/Y, and flashing brights by pulling back on the stalk works as well. I rarely used the pushing forward motion in my 3 to enable/disable automatic brights, so instead I actually made that into a Homelink trigger, and it is absolutely awesome.

I'll need time to get it written up, and there is some basic soldering involved. I'm using a Particle Photon + Carloop to read the state of the stalk and send CAN messages to the car, so nothing stock is modified and the change is entirely reversible. I'll create a git repo with the instructions to recreate the work and a BoM.

Note: I have zero interest in selling or supporting this, so it will be an entirely DIY endeavor if folks want to do it. However, I do expect that approx 3 days after I publish the info, you'll be able to buy one on alibaba.

This is an UNLISTED youtube link, so please don't share beyond the forum for now. I am planning to do a better quality video about the project soon.

Absolutely incredible work. I will probably do this. How much are parts?
Nice work on integrating HomeLink as well. Could it do other things, like skip track, activate backup camera, etc? Can it text my wife and tell her I will not be home because I am busy playing with my car?
 
Absolutely incredible work. I will probably do this. How much are parts?
Nice work on integrating HomeLink as well. Could it do other things, like skip track, activate backup camera, etc? Can it text my wife and tell her I will not be home because I am busy playing with my car?
I probably spent $200 but I bought a new SCCM, which isn't really necessary if you can find the stalk modules themselves. I did not expect that they would literally snap in to the Plaid SCCM as they do. :)

I had the electronics laying around so those would have to be purchased and aren't factored into the $200. A carloop+particle is approx $50 iirc.

Other than that, I actually wired up modular RJ45 jacks because I had them laying around and it was easy, but a more robust connector setup from Mouser is on the way. I'm going to use the actual yellow connector tesla uses instead of my current temporary solution. If doing proper connectors, add approx $20.
 
Hey, so the turn signal stalk is all wired up and works! It I also have wiper control button working exactly as it does on the 3/Y, and flashing brights by pulling back on the stalk works as well. I rarely used the pushing forward motion in my 3 to enable/disable automatic brights, so instead I actually made that into a Homelink trigger, and it is absolutely awesome.

I'll need time to get it written up, and there is some basic soldering involved. I'm using a Particle Photon + Carloop to read the state of the stalk and send CAN messages to the car, so nothing stock is modified and the change is entirely reversible. I'll create a git repo with the instructions to recreate the work and a BoM.

Note: I have zero interest in selling or supporting this, so it will be an entirely DIY endeavor if folks want to do it. However, I do expect that approx 3 days after I publish the info, you'll be able to buy one on alibaba.

This is an UNLISTED youtube link, so please don't share beyond the forum for now. I am planning to do a better quality video about the project soon.

Very creative. Great work and thanks for sharing. I'm not sure you could do all that on a traditional vehicle...ICE, etc...
 
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Hey, so the turn signal stalk is all wired up and works! It I also have wiper control button working exactly as it does on the 3/Y, and flashing brights by pulling back on the stalk works as well. I rarely used the pushing forward motion in my 3 to enable/disable automatic brights, so instead I actually made that into a Homelink trigger, and it is absolutely awesome.

I'll need time to get it written up, and there is some basic soldering involved. I'm using a Particle Photon + Carloop to read the state of the stalk and send CAN messages to the car, so nothing stock is modified and the change is entirely reversible. I'll create a git repo with the instructions to recreate the work and a BoM.

Note: I have zero interest in selling or supporting this, so it will be an entirely DIY endeavor if folks want to do it. However, I do expect that approx 3 days after I publish the info, you'll be able to buy one on alibaba.

This is an UNLISTED youtube link, so please don't share beyond the forum for now. I am planning to do a better quality video about the project soon.

Fantastic work!! I am also very interested in how this can be accomplished.

Quick question: what's sticking out behind the yoke, a little higher than middle part above the column? Will it remain there once you're done with the project?
 
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Oh yeah, turning on Sentry mode will definitely prevent the car from sleeping, so there will most likely still be power to the diag port.

If you let the car sleep though (turn off Sentry and other API pings such as Tesla app or 3rd-party sites), power to the diag port should drop.
This is interesting as I was looking for power for a dash cam (Blackvue) that is semi switched. I would like it off when at home (sentry would be off there) and on when the car is parked somewhere else (sentry is on).

In my prior MS 2017 it was on 24 x 7 which is fine, but seems 99% of the time my car is just sitting in my garage…so this would power off the cam at that time… best of both worlds.
 
This is interesting as I was looking for power for a dash cam (Blackvue) that is semi switched. I would like it off when at home (sentry would be off there) and on when the car is parked somewhere else (sentry is on).

In my prior MS 2017 it was on 24 x 7 which is fine, but seems 99% of the time my car is just sitting in my garage…so this would power off the cam at that time… best of both worlds.
Very interesting thoughts. I got broken into at home though, so I now leave Sentry mode on there too. :mad: