Since we all want to reduce the chance of theft, and because we know that access to the OBD II port is the primary mode of attack for low-effort thieves, why not remove that access.
The factory OBD II port is held in place with two clips that are easily depressed from the cabin-side. I did it with my fingers. Once depressed, you can remove the OBD II port from the rear and gain access. That access looks like this:
From here you can either intercept data wiring to route to an interrupt switch (like a 4-pole toggle to remove data access), or you can hide this harness, or you can de-pin, whatever you want to eliminate useful access for a thief.
There are only eight wires used in this 2023 1SS, as shown here:
And the schematics for this port are as follows:
Removing this port from the socket and hiding it is free. It may be enough to deter a thief who is looking for an easy job. A missing port may cause them to go looking, or may deter them to look for an easier job. You can hide the port in several locations and then simply unhide to provide access to a shop or tech for actual service. If you have a range device to deactivate AFM, hiding the port may be handy if you don't like the light. Whatever your reason, this is a free step that may just make the difference between a 60 second job and a walk-away abort.
You may also feel like installing a fake port in place of the OEM port is a good deterrence, since a thief will notice the missing port andmay go looking. I would be better if the port had a functional 12V and ground so their tool would power up. You could even add some 10k ohm resistors between the data pins so it looked like something was there. Good news, you can buy the OEM port, pins, and retainer for a few dollars form Mouser Electronics.
And if you want to pin this to provide voltage so it appears as if it might work, and looks like it has pins, you can get the pins and retainer here also.
**UPDATED** The Pin information I shared previously is reported to be incorrect. I apologize for that confusion, I was referencing service information and the pin compatibility on Mouser. Below is user confirmed pin compatibility:
WM3324CT-ND
https://www.mouser.com/ProductDetail/Molex/0504208000
I have ordered the items above and will report back once received for a verification of fitment, but the part number is from the GM service manual and looks identical.
I do not recommend you do the following. This is the "do not do this" portion of the post:
Once you have pins and the replacement OBD II port, there is nothing stopping you from re-wiring this port with reverse polarity, meaning you put 12V on the ground and signal pins and then ground the 12V pin while serving the 12V side from a dedicated fuse at the battery (sized for the wire used). Doing this is not advised as it would destroy the tool being used to steal your car, or a tool used by an actual service tech to fix your POS. The latter is why a cover indicating access is not advised is strongly recommended.
Even with a cheap cover indicating that access is not recommended, you may be liable for damages that occur to scan tools that are connected to your booby-trap. Don't do this, even if you're tempted to. PSA over
The cheap cover may be recommended with the hidden port, to protect the pins from being shorted out. This depends on where you relocated the port.