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I’ve found the 12v on the Tesla diagnostic port (the one by the wireless charger) does shutdown after a period of time. Thanks.
I just wired up my detector today to the OBDII port in the foot well. Yellow and black wire, just taped into them and ran the wire up the A-pillar so I did not use a connector and the connection is hidden behind the paniel. volt meter showed it turned off when the doors shut and no one is inside seated. no errors reported. Don’t be fooled, if you sit inside and close the doors it will stay on and that might make you think it’s not switched. I turned on sentry mode and watched through the window and it looked to be off.
 
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HankLloydRight

No Roads
Supporting Member
Jan 18, 2014
13,545
11,986
Connecticut
I'm certain the actual OBDII port is unswitched in Model S/X. I think you may have tapped a different wire or don't have accurate results with your voltmeter.
I've sold dozens of my PWS (see sig link) for MS/MX all connected to the OBDII port as they are "always on" devices and the OBDII port is definitely unswitched.
What year/model do you have?
 
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I'm certain the actual OBDII port is unswitched in Model S/X. I think you may have tapped a different wire or don't have accurate results with your voltmeter.
I've sold dozens of my PWS (see sig link) for MS/MX all connected to the OBDII port as they are "always on" devices and the OBDII port is definitely unswitched.
What year/model do you have?
In my p100d there was switched and perm in the obd - I used to run my dashcam from it
 

4SUPER9

2022 Model S
Jun 6, 2013
3,372
3,308
So Cal
I'm certain the actual OBDII port is unswitched in Model S/X. I think you may have tapped a different wire or don't have accurate results with your voltmeter.
I've sold dozens of my PWS (see sig link) for MS/MX all connected to the OBDII port as they are "always on" devices and the OBDII port is definitely unswitched.
What year/model do you have?
I am using the same OBD connector as before, and it is now switched. I will test the other wires though.
 
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I'm certain the actual OBDII port is unswitched in Model S/X. I think you may have tapped a different wire or don't have accurate results with your voltmeter.
I've sold dozens of my PWS (see sig link) for MS/MX all connected to the OBDII port as they are "always on" devices and the OBDII port is definitely unswitched.
What year/model do you have?
Mine is a 2021 model s plaid. It seems to be switch as far as I can tell. My meter is correct as I am an electronics engineer for the last 35 years and spent 10 years design stuff for AEM. Not that i haven’t missed things before but it’s unlikely. The detector turns off as it should when I am out of the car and doors are closed. I believe it was pin-1 on the connector. This is my first Tesla though.
 

Krash

Data Technician
Moderator
Apr 18, 2017
2,634
2,993
Intermountain US
Anyone have information about the OBD CAN bus? What information is on that CAN bus? Just curious.
See the section titled CANBus DBC Files and Similar on the first post of this thread.
You can check out EVERYTHING you can learn from your Tesla's can bus at…
Keep in mind that DBC files are model, year and firmware specific. Some 3/Y use that version. 2022 S/X use something similar. For pre 2022 S/X see that CANBus DBC Files and Similar section for earlier DBC files.
 
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From another thread (SMT) on other cable sources. I was looking for a 2022 TMY for one of my kids future delivery.

EVoffer now offers a cable for palladium 2021 S/X cars, as well as the new can connectors hidden in 2021 3/Y, and it does support multiple busses with canserver too!


ScanMyTesla / CANserver users:
FYI, EVoffer added a page for the Y/3. The picture on that page will be updated when they have the new cable. Past EVoffer comment: "We have found a power source nearby. We will add a pair of connector{s} for powering up the OBD device"

>>>>
Model 3 2021+
  • Made in USA built after 2020/10/05; or
  • Made in China built after 2020/12/28
Model Y 2021+
  • Made in USA built after 2021/01/13; or
  • Made in China built after 2020/12/14
<<<<
 
So perhaps I'm just blind but i cant seem to find the parts or wiring diagram for a 2021 model 3. I built an adapter cable some time back for my car and it works great on SMT but i want to make on for my friends car but i seem to be going full retard and cant find the diagram of what wire connects to what wire and the plug i need to get. I know mouser sold me the connector and pins for my model S one but i know the 3 is different. I like to build my own stuff instead of buy one whenever its possible.
 
So perhaps I'm just blind but i cant seem to find the parts or wiring diagram for a 2021 model 3. I built an adapter cable some time back for my car and it works great on SMT but i want to make on for my friends car but i seem to be going full retard and cant find the diagram of what wire connects to what wire and the plug i need to get. I know mouser sold me the connector and pins for my model S one but i know the 3 is different. I like to build my own stuff instead of buy one whenever its possible.
What are you trying to connect to? Wiring diagram requires paying tesla $30 or so.

Connector info here: MCU Connector Information – Analytic.lol Feel free to DM.
 
What are you trying to connect to? Wiring diagram requires paying tesla $30 or so.

Connector info here: MCU Connector Information – Analytic.lol Feel free to DM.
Pretty cool link but I'm referring to the diag port oen, on my car it's the unused plug under the MCU. And someone posted a diagram on here somewhere of what line goes to what line on the OBD2 port. I need that except for a 2021 Model 3.
 
Pretty cool link but I'm referring to the diag port oen, on my car it's the unused plug under the MCU. And someone posted a diagram on here somewhere of what line goes to what line on the OBD2 port. I need that except for a 2021 Model 3.
You mean the new blue CAN connector to the right/below the MCU/ICE ? I think that is the most recent one mentioned here - Diagnostic Port and Data Access

There is no OBDII interface though - You can use a special app though along with a CAN to OBDII intercept to read that data if you'd like
 
You mean the new blue CAN connector to the right/below the MCU/ICE ? I think that is the most recent one mentioned here - Diagnostic Port and Data Access

There is no OBDII interface though - You can use a special app though along with a CAN to OBDII intercept to read that data if you'd like
Yeah what I'm looking for is the exact same thing i have for my car (14 S P85D) that has a CAN plug on one side an an OBD2 plug on the other side that a Bluetooth OBD2 reader plugs into so i can use scan my tesla on my phone. except i need the pinout for a newer model 3
 
Yeah what I'm looking for is the exact same thing i have for my car (14 S P85D) that has a CAN plug on one side an an OBD2 plug on the other side that a Bluetooth OBD2 reader plugs into so i can use scan my tesla on my phone. except i need the pinout for a newer model 3
You need something like this which bridges the connection under/behind the center console, unless you're building a custom solution in which case you can grab the wiring diagram from Tesla for $30 OHP OBD2 Adapter Splitter for Tesla Model 3 & Y | 2019 - 2021 Build
 
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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!
FWIW, I tried plugging in the OBDLink LX to the physical OBD2 port on a 2022 Model S LR and it would not work using the Scan My Tesla App. Also tried using an adapter cable that mapped pins 18 and 19 of the Blue Diagnostics connector which also didn't work. I'm debating if I should try moving the adapter pins from 18,19 to either 13,14 or 9,10.
 
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