12V Access: Model S 2021 Refresh

[WiLz]

Question for the ignorant, if you used a hotspot rather than premium connectivity, is the car still constantly connected? For example, would you still have dynamic traffic routing in navigation via google? My understanding is no, but I'm not very knowledgeable in these things.

From what I have seen, you lose live traffic. It does not show up for me even when connected to wifi. You just gain back ability to play streaming music and watch streaming videos. The wifi connection is also glitchy, the car tends to automatically disable wifi when you start driving. And even when connected to hotspot, it will randomly lose connection, and your streaming music will stop playing, until you manually reconnect and restart the music. So definitely not as good as having premium connectivity.

 

[headcase]

From what I have seen, you lose live traffic. It does not show up for me even when connected to wifi. You just gain back ability to play streaming music and watch streaming videos. The wifi connection is also glitchy, the car tends to automatically disable wifi when you start driving. And even when connected to hotspot, it will randomly lose connection, and your streaming music will stop playing, until you manually reconnect and restart the music. So definitely not as good as having premium connectivity.

Good catch about loosing live traffic. That is BS, given the car is still connected. I suspect this impacts routing decisions by the nav computer. Grrrr...

If I go into settings and hit the check box to have the car stay connected to the hotspot when in drive, it stays connected consistently for me. I use it all the time to access the HiFi tier of Tidal on the dash.

 

[n2mb_racing]

Has anyone found a higher amperage 12V tap point? I looked through the schematics on service.tesla.com and it doesn't seem like there is an obvious +12V lug to tap into, like on the Model 3.

IF I am reading the schematics right, it looks like the amplifier 12V supply might be the best bet. I think it is a 3 mm2 wire, if am interpreting the code correctly, indicating about 12 awg. Maybe good for 40A? But, no idea since they don't have a traditional fuse box. See diagram below.

Also, silly question, where is the external amp?

Any other good circuits to consider that are powered most of the time or at least whenever the car is awake (sentry mode) ?

 

[bassmaster]

Has anyone found a higher amperage 12V tap point? I looked through the schematics on service.tesla.com and it doesn't seem like there is an obvious +12V lug to tap into, like on the Model 3.

IF I am reading the schematics right, it looks like the amplifier 12V supply might be the best bet. I think it is a 3 mm2 wire, if am interpreting the code correctly, indicating about 12 awg. Maybe good for 40A? But, no idea since they don't have a traditional fuse box. See diagram below.

Also, silly question, where is the external amp?

Any other good circuits to consider that are powered most of the time or at least whenever the car is awake (sentry mode) ?

Why don't you use the wires comming from the Battery?

 

[n2mb_racing]

Why don't you use the wires comming from the Battery?

On the refresh S/X and probably the new 3/Y with the lithium ion 12v battery you can't draw more than a few amps from the battery before the computer complains or you drain the battery. The charging current to the 12v is very limited. It's separate from the rest of the 12v dcdc system.

 

[bassmaster]

On the refresh S/X and probably the new 3/Y with the lithium ion 12v battery you can't draw more than a few amps from the battery before the computer complains or you drain the battery. The charging current to the 12v is very limited. It's separate from the rest of the 12v dcdc system.

I've got here a 16V battery out of a Model Y with a dead BMS. I was able to get 60A from the battery - maybe more, but my test equipment was limited to 60A.

 

[bassmaster]

As far as I can see, the cells are CATL NMC 6,9Ah with 50C. So 345A should be ok.

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[n2mb_racing]

As far as I can see, the cells are CATL NMC 6,9Ah with 50C. So 345A should be ok.

Dieses Produkt ist nicht mehr verfügbar.

Dieses Produkt ist nicht mehr verfügbar.

german.alibaba.com

Yes, you can pull high peak current from the battery, but others have reported the charging current is limited to about 6a, so you won't be able to pull much sustained power from the battery.

 

[n2mb_racing]

OK, finally think I figured out why the new 12V (15v) battery is Li-ion rather than Lifepo. I think they needed that ridiculous high current capability to be able to (briefly) run the autopilot computer, power steering, and power brakes in the event that the main pack or the DC/DC converter fails while on AP. All of those things probably require a fair amount of peak power. They need just enough capacity to bring the car to a stop safely. I don't think many lifepo cells have that kind of peak discharge capabilities. Maybe that was obvious, but just occurred to me.

Anyway, will go back to look at the amp wiring. I'm planning to add an XT-60 plug to the amp power wire so that I can occasionally plug in things like a 12V inverter for portable / emergency power.

 

[AcesAreWld]

OK, finally think I figured out why the new 12V (15v) battery is Li-ion rather than Lifepo. I think they needed that ridiculous high current capability to be able to (briefly) run the autopilot computer, power steering, and power brakes in the event that the main pack or the DC/DC converter fails while on AP. All of those things probably require a fair amount of peak power. They need just enough capacity to bring the car to a stop safely. I don't think many lifepo cells have that kind of peak discharge capabilities. Maybe that was obvious, but just occurred to me.

Anyway, will go back to look at the amp wiring. I'm planning to add an XT-60 plug to the amp power wire so that I can occasionally plug in things like a 12V inverter for portable / emergency power.

I did exactly that — an XT60 I mounted in my front trunk to charge some small batteries, power a small inverter, etc... nothing more than a few hundred watts or the car will get upset with the unknown / unexpected current draw. I used 12 gauge wire coming right from the lithium "12V" battery through a 25A fuse to the front of the front-trunk. From there an XT60 breaks off power for my aftermarket power front trunk, the LED's I added to the front trunk, and then another XT60 mounted to the plastic plate the tow hook is in.

In addition to charging / powering THINGS with that XT60, I can ALSO back-feed to "jump" the "12V" lithium battery in the car if ever needed as well, and I keep a small battery backup pack in the front trunk to do that. I had an inverter go on my car and it blew the pyro fuse, and it was a real nightmare trying to keep the jump-pack ok the jump-post while getting the car on the tow-truck (in the POURING RAIN). As soon as the jump pack died or broke connection the electronic parking brake would re-lock the back wheels. This XT60 allows me to jump the 12V pack through it if needed.

 

[n2mb_racing]

I did exactly that — an XT60 I mounted in my front trunk to charge some small batteries, power a small inverter, etc... nothing more than a few hundred watts or the car will get upset with the unknown / unexpected current draw. I used 12 gauge wire coming right from the lithium "12V" battery through a 25A fuse to the front of the front-trunk. From there an XT60 breaks off power for my aftermarket power front trunk, the LED's I added to the front trunk, and then another XT60 mounted to the plastic plate the tow hook is in.

In addition to charging / powering THINGS with that XT60, I can ALSO back-feed to "jump" the "12V" lithium battery in the car if ever needed as well, and I keep a small battery backup pack in the front trunk to do that. I had an inverter go on my car and it blew the pyro fuse, and it was a real nightmare trying to keep the jump-pack ok the jump-post while getting the car on the tow-truck (in the POURING RAIN). As soon as the jump pack died or broke connection the electronic parking brake would re-lock the back wheels. This XT60 allows me to jump the 12V pack through it if needed. View attachment 880629View attachment 880631View attachment 880632

Interesting! Have you tried other circuits? Presumably the car won't complain about the DC power outlet, you can draw 12A continuous, 16A peak from it. I imagine either the audio amp or seat heater circuits would also support a lot of current, but they could be monitored and complain if the draw is unexpectedly high.

 

[vcor]

While I wasn't looking for a high-power source, I did test a number of places and validated when they supplied power and recorded when they powered off. I tested new cars S/X/3/Y and some older models too. I also did current tests too. Here are all my results: Accessory Power Guide 12v/5v – TeslaTap More useful for a dashcam or radar detector than drawing massive power.

 

[AcesAreWld]

Interesting! Have you tried other circuits? Presumably the car won't complain about the DC power outlet, you can draw 12A continuous, 16A peak from it. I imagine either the audio amp or seat heater circuits would also support a lot of current, but they could be monitored and complain if the draw is unexpectedly high.

I have not tried any others, no. My understanding that basically everything was monitored by the car (after all, there are no fuses) and if the draw is outside what the car expects, it will "complain" / shut down that circuit / chaos ensues / etc.

I wanted to pull power from the "Penthouse" — the 12V output straight from the pack before it goes to any other circuits like you can under the back seat of a Model 3 — but there was no easy, obvious, clear access to that port on the new Model S Plaid that I could find (it's somewhere up front in a very hard place to get to, I believe).

So... drawing a few hundred watts (tops) off the XT60 was the best I could do for now... and I accepted that ... for now.

 

[n2mb_racing]

I have not tried any others, no. My understanding that basically everything was monitored by the car (after all, there are no fuses) and if the draw is outside what the car expects, it will "complain" / shut down that circuit / chaos ensues / etc.

I wanted to pull power from the "Penthouse" — the 12V output straight from the pack before it goes to any other circuits like you can under the back seat of a Model 3 — but there was no easy, obvious, clear access to that port on the new Model S Plaid that I could find (it's somewhere up front in a very hard place to get to, I believe).

So... drawing a few hundred watts (tops) off the XT60 was the best I could do for now... and I accepted that ... for now.

Got it. Yeah, I've tested pulling power from the Model 3 DC/DC and was able to do >600 watts sustained.

A reliable few hundred watts is pretty good, though. I think the usual 12V power outlet connections are unreliable and would worry that you might end up with a bad connection that melts the receptacle, even if you are only pulling 12A continuous. I might tap into that wire at the back of the outlet using an XT60 for a more reliable connection.

 

[AcesAreWld]

Got it. Yeah, I've tested pulling power from the Model 3 DC/DC and was able to do >600 watts sustained.

A reliable few hundred watts is pretty good, though. I think the usual 12V power outlet connections are unreliable and would worry that you might end up with a bad connection that melts the receptacle, even if you are only pulling 12A continuous. I might tap into that wire at the back of the outlet using an XT60 for a more reliable connection.

I'd be interested to know what gauge wire they have going to that 12V power outlet!

 

[n2mb_racing]

I'd be interested to know what gauge wire they have going to that 12V power outlet!

If I'm interpreting the wiring diagrams correctly, they list 2.0, which I am interpreting to mean 2mm sq, which is between 14 and 16 awg. They also say the main 12V battery wires are 25 mm sq, which would be 4 awg, which seems too thick.

 

[AcesAreWld]

If I'm interpreting the wiring diagrams correctly, they list 2.0, which I am interpreting to mean 2mm sq, which is between 14 and 16 awg. They also say the main 12V battery wires are 25 mm sq, which would be 4 awg, which seems too thick.

Interesting.

Hey — I used my XT60 this past weekend to charge up my 300wh battery pack / inverter / backup / charger pack. It pulled up to about 120 watts from the XT60 while the car was parked and sentry mode was on (car never fully went to sleep since Sentry was on). No complaints from the car, all was good, charged it from about 60% to 100%.

 

[4SUPER9]

I did exactly that — an XT60 I mounted in my front trunk to charge some small batteries, power a small inverter, etc... nothing more than a few hundred watts or the car will get upset with the unknown / unexpected current draw. I used 12 gauge wire coming right from the lithium "12V" battery through a 25A fuse to the front of the front-trunk.

Can you please describe/show how you specifically tapped into power from the battery?

 

[SDRick]

Nice set up Aces.

It is a shame though that you need to purchase that expensive "small" portable battery pack and haul it around when the potential of something much better is already in the car..

Too bad Tesla does not include decent AC, offer it as a option, or that some third party hasn't come up with an elegant solution for probably less than you paid for for the portable unit!

 

[AcesAreWld]

Can you please describe/show how you specifically tapped into power from the battery?

I tapped into negative at an existing vehicle ground location (shown in photo) and for 12V+ I tapped into the car's 12V jump point my soldering a flat metal connector to the end of my wire and then using the OEM protective cap to hold it in place on the jump post. It's not my favorite part of the install, but it seems to be working reliably with no loss of connection. I labeled some of the parts and traced the path in the attached photo...