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Spare Switched 12V Circuit on Model S built after July 2014

wk057

Vendor & Senior Tinkerer
Feb 23, 2014
6,069
14,206
Hickory, NC, USA
According to a Tesla "Tech Note" that was passed along to me, there is a 12V power source under the center console area in newer vehicles... I'll copy and paste that info since it seems pretty relevant here, appears to be for end users (since it specifically says Tesla isn't allowed to install third party equipment...) and I'm going to figure Tesla isn't going to mind. I haven't seen this posted elsewhere, and the document doesn't contain any language that would seem to prohibit passing it along like some of the other things I have seen.

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Tech Note: Spare 12V Power Circuit


Tech Notes are announcements that help to communicate and track new information about Tesla Service concerns. Such concerns may or may not be VIN specific. These instructions assume knowledge of motor vehicle and high voltage electrical component repairs, and should only be executed by trained professionals. Tesla Motors assumes no liability for injury or property damage due to a failure to properly follow these instructions or for repairs attempted by unqualified individuals.

All Model S vehicles built after approximately July 11, 2014 are equipped with a spare 12V power circuit. The purpose of this power circuit is to provide a switched power source, reducing the risk of vehicle damage due to improperly installed third-party equipment.

To access the spare 12V power circuit, remove the RH center console closeout extension. The spare 12V positive circuit is the red wire with a white stripe on the gray 4-pin connector with 3 wires. NOTE: The spare 12V circuit shares the same black ground as the center console auxiliary outlet.


The spare 12V power circuit is tied to the accessory (ACC) rail and is capable of up to 11 A (150 W) of continuous load, 15 A (180 W) peak load.

NOTE: The spare 12V power circuit is protected by fuse F33 in fuse box 2 (Figures 2 and 3). Remove the rear underhood center apron to access fuse box 2

tnphoto.jpg


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WARNING
: Use of improper external cabling or unsafe charging outlets can expose passengers to injury from high voltage electricity.
CAUTION: Tapping into the 12V system, including the spare 12V power circuit, is done solely at the user’s risk and can result in increased draining of, or potential damage to, the 12V battery. Potential effects of modifying Model S with third-party components can include, but are not limited to, reduced driving range and increased electromagnetic interference (EMI).
NOTE: Tesla does not endorse the use of third-party equipment and does not accept any responsibility for any damage incurred from installing non-OEM equipment.
NOTE: Tesla employees are not permitted to install or assist in installing third-party equipment.

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Hopefully someone finds this useful, since it seems a little odd to have a user-oriented informational note not actually posted anywhere that I could see....
 

pgiralt

Active Member
Supporting Member
Jun 16, 2013
1,521
157
Cary, NC
Nice find. I guess Tesla is in a difficult position on this one. They don't want to advertise something that is to be used for something they don't endorse, yet they went out of their way to actually create this circuit for the specific purpose of 3rd party components.

I wonder if this was added for the Taxis they deployed in the Netherlands. I would think you'd need some equipment for the meter and other such equipment. I think they went into service around October 2014, so a July build would be just about right to build and ship to Europe. Maybe they did this for commercial applications and they provide the tech note to certain 3rd parties that install that gear? Just a thought.
 
According to a Tesla "Tech Note" that was passed along to me, there is a 12V power source under the center console area in newer vehicles... I'll copy and paste that info since it seems pretty relevant here, appears to be for end users (since it specifically says Tesla isn't allowed to install third party equipment...) and I'm going to figure Tesla isn't going to mind. I haven't seen this posted elsewhere, and the document doesn't contain any language that would seem to prohibit passing it along like some of the other things I have seen.

---

Tech Note: Spare 12V Power Circuit


Tech Notes are announcements that help to communicate and track new information about Tesla Service concerns. Such concerns may or may not be VIN specific. These instructions assume knowledge of motor vehicle and high voltage electrical component repairs, and should only be executed by trained professionals. Tesla Motors assumes no liability for injury or property damage due to a failure to properly follow these instructions or for repairs attempted by unqualified individuals.

All Model S vehicles built after approximately July 11, 2014 are equipped with a spare 12V power circuit. The purpose of this power circuit is to provide a switched power source, reducing the risk of vehicle damage due to improperly installed third-party equipment.

To access the spare 12V power circuit, remove the RH center console closeout extension. The spare 12V positive circuit is the red wire with a white stripe on the gray 4-pin connector with 3 wires. NOTE: The spare 12V circuit shares the same black ground as the center console auxiliary outlet.


The spare 12V power circuit is tied to the accessory (ACC) rail and is capable of up to 11 A (150 W) of continuous load, 15 A (180 W) peak load.

NOTE: The spare 12V power circuit is protected by fuse F33 in fuse box 2 (Figures 2 and 3). Remove the rear underhood center apron to access fuse box 2

View attachment 81724

--

WARNING
: Use of improper external cabling or unsafe charging outlets can expose passengers to injury from high voltage electricity.
CAUTION: Tapping into the 12V system, including the spare 12V power circuit, is done solely at the user’s risk and can result in increased draining of, or potential damage to, the 12V battery. Potential effects of modifying Model S with third-party components can include, but are not limited to, reduced driving range and increased electromagnetic interference (EMI).
NOTE: Tesla does not endorse the use of third-party equipment and does not accept any responsibility for any damage incurred from installing non-OEM equipment.
NOTE: Tesla employees are not permitted to install or assist in installing third-party equipment.

---

Hopefully someone finds this useful, since it seems a little odd to have a user-oriented informational note not actually posted anywhere that I could see....

Shhhhhh, this was supposed to be a secret. And this is why we cant have nice things.
 
This is great. I am installing trailer lights, the setup I have steals the signal from the brake & signal wires in the back but draws the power from a separate source, for which I will use this swtched 12v source. I've pulled the wire from the front console to the back of the car but there is not a pin in that connector where I would connect my wire. Any ideas where I could get a pin that would fit it?

Thanks
 

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