12v constant in rear trunk

[Tummy]

I want to mention that on our car, produced August 2016, the hatch wire is solid gray, not red and gray. There were two boxes in our car and the red gray wire went into a box labeled parking sensor. I tapped that one first but it didn’t work. The gray wire in the other box was for our hatch and worked.

 

[MattMatt]

I want to mention that on our car, produced August 2016, the hatch wire is solid gray, not red and gray. There were two boxes in our car and the red gray wire went into a box labeled parking sensor. I tapped that one first but it didn’t work. The gray wire in the other box was for our hatch and worked.

My March 2017 S90D matched this description. And I took a few pictures in case it helps some one else out. I was able to do this with fully removing the carpet, I just peeled it back from the seat side towards the trunk until I could access the wires I needed.

Here is the connector:

And pulled out showing the grey wire I tapped off of:

Matt

 

[bjornb]

I can confirm that it is the grey connector:


One can also see the ground connector used (to the right of the two black boxes):

 

[Akikiki]

bjorb, I used the same lead coming off the liftgate controller that you did from your picture. However, I then fed that large lead into a 4 position fuse box so I could tap the same liftgate connection (if needed) for another power source. This saves scrounging around for different source or coming back in behind the trunk fuzzy later.

 

[langineers]

I found my red w/gray stripe on my 2015 MS P85D was the only hot wire with my car sleeping, but it is not a direct connection to the aux battery. Unfortunately I removed the ground post retaining nut which lossened and lifted the ground lead to both the parking controller and the lift gate controller 2 bad things happened: 1) the lift gate would beep when triggered but not activate the motor (a car power cycle fixed that) and. 2) the parking brakes got stuck engage. Power cycling did no fix that and Tesla tech on the phone stated after a brief look at the logos, he thought the CAN bus was signalling the parking brakes to stay on. Strangely, the instrument cluster displays an error that the parking brakes are stuck off. In retrospect, I should have used PoisTaps on both the so called constant hot and the ground lead instead of unplugging any connectors and lifting the ground legs which I am certain caused the problem. Car was towed off my driveway in wheel dolly’s back to the SC.

While waiting for the tow truck I tested a pure sine wave inverter and found the 14-16 gauge wire (red w/gray stripe) had just enough current to get 100 watts load (good enough to charge my Boosted Board) but not enough to attempt to drive a 360 watt load to charge my eBike. At 130 watts the voltage dropped below 12VDC shutting down the inverter.

This means I still need to locate a firewall penetration to get a heavy gauge cable from the aux battery to the rear cabin.

 

[Xenoilphobe]

Switched 12v power line to tap into?

 

[[email protected] Bargain]

The Power liftgate module has a good source of +12v always on. Even if your car doesn't have the option, the connector is still there. It's located on top of and behind the right rear wheel arch and can be accessed by pulling the carpet piece out there. (must remove plastic trim to do this)

I have also retrofitted a 12V output from the liftgate supply on my car

That's great, I really want to add a 12V socket to my trunk for the cooler as well. I have just taken a look, the cooler requires max. 48W. Does it require an additional fuse to connect a 12V socket to the power liftgate module, and if yes which one?

 

[morrisdl]

Thanks for the tips. I just did this mod yesterday for fridge power. Also wanted options for constant USB charging and rear seat power. I ended up going with CAN bus tap. This one is really low profile and the wire tucks back under the dash covers:

GPSit OBD II OBD2 Power Adapter Harness
by GPSit
Link: http://a.co/6b72Zlw

All the center trim panels just popoff, except above the brake pedal is one torx screw.

 

[Akikiki]

I found my red w/gray stripe on my 2015 MS P85D was the only hot wire with my car sleeping, but it is not a direct connection to the aux battery. Unfortunately I removed the ground post retaining nut which lossened and lifted the ground lead to both the parking controller and the lift gate controller 2 bad things happened: 1) the lift gate would beep when triggered but not activate the motor (a car power cycle fixed that) and. 2) the parking brakes got stuck engage. Power cycling did no fix that and Tesla tech on the phone stated after a brief look at the logos, he thought the CAN bus was signalling the parking brakes to stay on. Strangely, the instrument cluster displays an error that the parking brakes are stuck off. In retrospect, I should have used PoisTaps on both the so called constant hot and the ground lead instead of unplugging any connectors and lifting the ground legs which I am certain caused the problem. Car was towed off my driveway in wheel dolly’s back to the SC.

While waiting for the tow truck I tested a pure sine wave inverter and found the 14-16 gauge wire (red w/gray stripe) had just enough current to get 100 watts load (good enough to charge my Boosted Board) but not enough to attempt to drive a 360 watt load to charge my eBike. At 130 watts the voltage dropped below 12VDC shutting down the inverter.

This means I still need to locate a firewall penetration to get a heavy gauge cable from the aux battery to the rear cabin.

This is really good info. I agree with you about grounding issues like you encountered. I am not going to explain why, but I had some bad experiences with grounding here. I decided to never loosen any bolt or terminal that is used as a ground. What I do instead, is find a place or drill a fresh hole for a self tapping screw or bolt/nut and create my own ground. Yes, of course, I am doubly careful not to penetrate the body or a wire when drilling. I wish more folks had a chance to read and understand what you are saying in your post because its that important. Yes, and having to have your car towed to the SC and corrected is the consequences of messing with the existing component groundings. Especially when there still so many components and connections that we don't understand. I hope for you that your visit to the SC was not costly.

 

[Akikiki]

That's great, I really want to add a 12V socket to my trunk for the cooler as well. I have just taken a look, the cooler requires max. 48W. Does it require an additional fuse to connect a 12V socket to the power liftgate module, and if yes which one?

My two cents. Any time you think that maybe it would be wise to add a fuse, - ADD the FUSE. Its just added safety of the car and your device.

 

[[email protected] Bargain]

Thanks for the tips. I just did this mod yesterday for fridge power. Also wanted options for constant USB charging and rear seat power. I ended up going with CAN bus tap. This one is really low profile and the wire tucks back under the dash covers

Unfortunately I can not see any pictures you posted. I assume you need to be logged in somewhere else to be able to view them?

If the liftgate isn't in operation, it's safe to draw up to 30A on this system. If the liftgate is in operation, I'd limit my max draw to about 10A peak. Since the liftgate only operates very intermittently, it's usually fine for electric coolers, HAM equipment, etc.

My two cents. Any time you think that maybe it would be wise to add a fuse, - ADD the FUSE. Its just added safety of the car and your device.

So would a 10A fuse be recommended in that case? Clearly the catch here is, that if you put a cooler into the truck connected to that 12V socket, you have to operate the truck liftgate while the cooler is in use.

 

[bjornb]

I would use a 7.5A or 10A fuse, that should be sufficient for a cooler (5A is on the low side, and may be too low for the start current when the compressor starts up).
Normally I think operating the liftgate at the same time should be fine, the highest currents is probably only seen when the liftgate is working hard, for example opening with a lot of snow on the liftgate, struggling against something when closing etc.

 

[Rijder]

Does anyone have a copy of the (no longer online available) EV-Appliqués installation manual that is mentioned in this thread? https://web.archive.org/web/20161021023441/http://www.evappliques.com/pages/installation

 

[morrisdl]

Does anyone have a copy of the (no longer online available) EV-Appliqués installation manual that is mentioned in this thread?

Lighted Rear Applique copy 2

 

[Akikiki]

AND... Ta-Da... The Lighted Rear Applique is still available at Tesla-Lights.net

 

[David.85D]

Is this the connector you mentioned?

View attachment 186069

I want to know what this is for! Found the same thing in the right rear corner of two Mod S so far.

 

[David.85D]

I found that connector by searching on Mouser: Find Electronic Components | Mouser
.

Thanks for finding this. I believe it mates to Molex 34695-0100. But that looks like a PCB header and a cable end. Do you know what pins the mate used? It appears to need two sizes. I’ve looked at the data sheet and can’t figure it out.

 

[IBUZA]

Thanks for finding this. I believe it mates to Molex 34695-0100. But that looks like a PCB header and a cable end. Do you know what pins the mate used? It appears to need two sizes. I’ve looked at the data sheet and can’t figure it out.

The 34695-0100 is supposed to be soldered into a circuit board. I believe it comes ready with 4x 2.8mm (.110") and 5x 1.5mm (.059") male connectors.

The 31372-1000 does not come with connectors. You have to order them separately. According to this document http://docs-europe.electrocomponents.com/webdocs/1371/0900766b81371519.pdf (page 6) it uses those female terminals:
1.50mm (.059") female – Molex 33012 -2001, -2002, -2003, -3001, -3002, -3003
2.80mm (.110") female – Tyco and Yazaki

Molex 33012 is easily found on Mouser.
I am not sure about the 2.80mm (.110") female terminal. I will order all of these to see if anything fits:
1326030-4 (Loose Piece) TE Connectivity | Mouser
1326032-4 TE Connectivity / AMP | Mouser
160626-1 TE Connectivity / AMP | Mouser
160668-2 TE Connectivity / AMP | Mouser
160625-2 TE Connectivity / AMP | Mouser

 

[David.85D]

Just to follow up. I emailed molex and they confirmed they only have the circuit board version of 34695-0100. No inline version available. Still should be easy to solder wires to the pins and heat shrink for stress relief..,

 

[IBUZA]

I emailed molex and they confirmed they only have the circuit board version of 34695-0100. No inline version available. Still should be easy to solder wires to the pins and heat shrink for stress relief..,

You are right. I used the circuit board version to make this ladaptor for two 12V-Outlets, since I do not like to tap into wires: