# Model Y wiring.



## Spiffywerks

When the Model Y was announced, they said they wanted to get rid of a substantial amount of wiring by switching to a new type of wiring harness (bus) for the car.

With the car looking like it’s using many of the same pieces from the Model 3, any of you think they are tabling the new harness to avoid delays of Model Y production? Or perhaps they are still working on it, hence the 2 years til production timeline?

I’m guessing the Model Y they showed at the reveal event was completely using Model 3 parts and the future production car will have changes to it.

I look forward to your comments and speculations!


----------



## JWardell

I that was announced with the early designs, and later they announced they canceled their plans to make Model Y very different and base it off the 3 instead. And they sure did.
I would guess it would have the same harnesses. But they could probably convert both to flex cables over time.


----------



## Steve S.

Personally, I doubt they would adopt the new wiring harness. I think that the Model Y on the reveal event is as close as it can be to be a production car. The biggest reason why it won't be in production soon is that Tesla wants to milk the Model 3 cow a bit longer given the resource and effort that have been put in the Model 3 development and production before Model Y cannibalizes it. They know Model Y will be a hot cake and have a good idea of how many they could sell annually in 2021 unless other automakers have some secret black horse from now to then, Tesla won't be in a hurry to push the schedule or pile further research and development onto Model Y.


----------



## cftarnas

Another reason they need time is the Model Y will be produced in the Nevada Gigafactory. It will be the first car produced there so there is likely a bit more ramp up time than if they had room to open a new line at Fremont. Smaller experiences labor pool (smaller overall) and general factory infrastructure improvements.


----------



## 11thIndian

JWardell said:


> I that was announced with the early designs, and later they announced they canceled their plans to make Model Y very different and base it off the 3 instead. And they sure did. I would guess it would have the same harnesses. But they could probably convert both to flex cables over time.


Not entirely true. Elon did announced the wiring harness modification in relation to the new platform (Q1 2017), but on the same earnings call that he announced that they were rolling back that decision (Q2 2017), he was asked if the electrical improvements were still on the table. He said,

_"We're going to aim for maximum carryover, but that's one of the things we would include. We would aim to switch out the 1.5 km of wiring harness for a redundant flex circuit that's more in the order of 100 meters or so."_

So as of August 2017, after the decision had been made to switch to the Model 3 platform, Tesla still planned to try and integrate the flex harness that would significantly reduce the complexity of the wiring.

We'll have to see if they stuck to that.


----------



## garsh

Steve S. said:


> I think that the Model Y on the reveal event is as close as it can be to be a production car. The biggest reason why it won't be in production soon is that Tesla wants to milk the Model 3 cow a bit longer given the resource and effort that have been put in the Model 3 development and production before Model Y cannibalizes it.


I think you are mistaken here. The Model Y is going to cost about the same to build as the Model 3, yet command a 10% price premium. The Y is going to be Tesla's cash cow, and they'll end up being very, very happy to have it cannibalize Model 3 sales.

.... they just need to make sure it doesn't start doing that until they start producing and selling them.


----------



## Scubastevo80

11thIndian said:


> Not entirely true. Elon did announced the wiring harness modification in relation to the new platform (Q1 2017), but on the same earnings call that he announced that they were rolling back that decision (Q2 2017), he was asked if the electrical improvements were still on the table. He said,
> 
> _"We're going to aim for maximum carryover, but that's one of the things we would include. We would aim to switch out the 1.5 km of wiring harness for a redundant flex circuit that's more in the order of 100 meters or so."_
> 
> So as of August 2017, after the decision had been made to switch to the Model 3 platform, Tesla still planned to try and integrate the flex harness that would significantly reduce the complexity of the wiring.
> 
> We'll have to see if they stuck to that.


I think the wiring upgrade boils down to a cost decision for them. While they certainly want to do it, the change needs to reduce cost, which seems to be a big focus at present. A more expensive wiring harness that no one sees is a difficult cost to pass along to the consumer.


----------



## JWardell

We also may be conflating two things: replacing bundled wire harnesses with flat flex cables, and moving the low voltage subsystem from 12 to 48v. The latter will probably not happen for another generation (and the industry as a whole has been wanting to do that for a while)


----------



## TrevP

They back off their plans to change to a new wiring system for the Y in order to bring it to market faster. They are likely improvements in the car for sure but that wiring thing is surely going to be implemented later on.


----------



## 11thIndian

August 2017 was definitely his last public statement Elon made on the Model Y electrical, but I’d definitely be willing to believe they eventually wore Elon down on this point. This is the type of innovation I was expecting him to talk about at the unveiling if he’d spent more than 5 min talking about the car. I could see them still doing it if it benefits them from a cost/complexity perspective. On the other hand I don’t want them to do anything that could potentially be a setback to production. 😄

From the owner perspective, I’m not sure what the difference would be except maybe reliability?


----------



## garsh

11thIndian said:


> From the owner perspective, I'm not sure what the difference would be except maybe reliability?


Material costs would be a little lower (less wiring). Production rate could increase (less wiring to install). Therefore, the end result for owners will be a lower price.


----------



## Love

OT:
Disappointed in the thread title...

Model Y'ring...it was _right there!_

/carry on


----------



## JWardell

11thIndian said:


> August 2017 was definitely his last public statement Elon made on the Model Y electrical, but I'd definitely be willing to believe they eventually wore Elon down on this point. This is the type of innovation I was expecting him to talk about at the unveiling if he'd spent more than 5 min talking about the car. I could see them still doing it if it benefits them from a cost/complexity perspective. On the other hand I don't want them to do anything that could potentially be a setback to production. 😄
> 
> From the owner perspective, I'm not sure what the difference would be except maybe reliability?


Weight, cost, simplicity of manufacturing, labor, weight, and cost, cost, and cost.


----------



## 11thIndian

All those things benefit Tesla. But if the Model Y ship with Model 3 wiring harness I don't know it makes any difference to the owner, unless it lowers price or reduces chance of failure. Tesla could internalize that savings to improve profit margin.


----------



## Guest

Model Y likely has very similar wiring harness as Model 3.
We already know that most parts are directly from Model 3.
It means that each and every electrical device (window lifters, door locks, accelerator pedal, screen etc)
has the same plugs and sockets.

I would note that looking and Model 3 simplicity (carried to Model Y as well) there is actually very little wiring
compared to "average high tech" german vehicles.
Solely removing main fuse box on Model 3 definitely reduced total wiring length by at least 15%.
I know almost every single wire on BMW's by heart and A LOT run through fuse box(es).

Airbag, Audio and some safety loops can not be "simplified". They must be kept as is.
But most things can be HEAVILY simplified. I have no information how much have been done on Model 3. 
Factory production line video is not detailed enough for analysis.


----------



## NEO

I'm not sure we can answer this question yet. Did you all see the article in Bloomberg about saving weight on Model 3? Tesla is always improving.


----------



## Deadbattery

JWardell said:


> We also may be conflating two things: replacing bundled wire harnesses with flat flex cables, and moving the low voltage subsystem from 12 to 48v. The latter will probably not happen for another generation (and the industry as a whole has been wanting to do that for a while)


I am guessing this means that CAN is not dead.... and as a result, the 12-volt system lives on, "12 volts isn't really good for anything" - Elon and the wire harness will be longer than 2 meters.

As a side note, I think this means your data collection project will work on both 3 and Y, yes?


----------



## JWardell

Deadbattery said:


> I am guessing this means that CAN is not dead.... and as a result, the 12-volt system lives on, "12 volts isn't really good for anything" - Elon and the wire harness will be longer than 2 meters.
> 
> As a side note, I think this means your data collection project will work on both 3 and Y, yes?


The 3 is already a reduction in CAN use and move some networks to more modern formats like ethernet and BroadR Reach. The Y might just duplicate everything with the three, or they take the opportunity to move things along even more. That would require a good amount of re-engineering though, especially for all of the components throughout the car that only communicate via can. Important things like the drive system. I doubt they will change that for the Y.
But you can rest assured as soon as the Y is in my driveway I will be diving into it as well!


----------



## CoastalCruiser

I would be quite circumspect on predicting the Model Y design at this early stage. In fact, the only thing I would be comfortable betting on is that the final design/specs will be different then what is being advertised today. Things change fast, especially at Tesla. Even Tesla may not know if the low voltage electrical system will be 12v or 48v. It's reasonable to assume that there is a "48v team" working in some cubbyhole somewhere. If they come up with a 48 rig that halves the cost of the current system (accounting for the odd local mini DC-DC converter for lagging hardware) then it's a fair bet it will show up in the car.... 75% component sharing be damned.

One tell might be how late in the game they build out the Model Y production line. If it comes later rather than sooner, it _may_ be an indicator that pencils are still up at this point. Maybe.


----------



## CoastalCruiser

cftarnas said:


> Another reason they need time is the Model Y will be produced in the Nevada Gigafactory. It will be the first car produced there so there is likely a bit more ramp up time than if they had room to open a new line at Fremont. Smaller experiences labor pool (smaller overall) and general factory infrastructure improvements.


Makes you wonder about the drive time to Sparks from Fremont, and how many experienced assembly workers will be at the G-factory, but commuting to Fremont on the weekends, since the [continuing] real estate boom in Reno priced them out of the market. This looks like a job for the Boring Company.


----------



## JWardell

CoastalCruiser said:


> I would be quite circumspect on predicting the Model Y design at this early stage. In fact, the only thing I would be comfortable betting on is that the final design/specs will be different then what is being advertised today. Things change fast, especially at Tesla. Even Tesla may not know if the low voltage electrical system will be 12v or 48v. It's reasonable to assume that there is a "48v team" working in some cubbyhole somewhere. If they come up with a 48 rig that halves the cost of the current system (accounting for the odd local mini DC-DC converter for lagging hardware) then it's a fair bet it will show up in the car.... 75% component sharing be damned.
> 
> One tell might be how late in the game they build out the Model Y production line. If it comes later rather than sooner, it _may_ be an indicator that pencils are still up at this point. Maybe.


To be clear increasing voltage will decrease the cost of the cables, not the system as a whole. The electronics will probably be about the same (bigger more expensive caps, but smaller bus bars, less copper?) You probably couldn't carry 80A to a steering rack with flex cable, but at 48V/20A maybe? Or those long runs to things in the back like your sub and amp would save a lot of cost and weight.

Tesla already suspiciously changed the connector I tap into from a 20 to a 28 pin in January...without adding any new wires. As if they were preparing the harness to be used in some new vehicle with a few more items to be added. So I think they are already implementing changes needed for model Y!


----------



## garsh

JWardell said:


> To be clear increasing voltage will decrease the cost of the cables, not the system as a whole.


For those who aren't as familiar with electricity, this is because a higher voltage allows you to carry just as much power, but over thinner (and thus lighter, smaller, and cheaper) wiring.


----------



## Guest

Switch to 48V is happening slowly. My bet is 2-4 more years until ramping will slowly begin.
Some things are already happening: starter-generator motor unit, electric turbocompressor,
electric air conditioner compressor and AFAIK steering rack.
Rear windscreen defrost, wiper motor, window lifters, cooling fan, HVAC fan - these are all WAITING 
First we need 48V hybridisation step. And then we will have more and more 48V stuff.
48V is coming. This year for sure.
My bet is that 12V battery will start to disappear in 2027-2028.
Though it doesn't mean 48V will definitely be non-lead based battery (thermal problems of li-based packs).


----------



## CoastalCruiser

Hopefully it comes faster than IPv6. Snort.


----------



## CoastalCruiser

So now here we are with the Cyber Truck on the books. Gives us a new product and timeline to consider for where all the electric tech considered in this thread may land.


----------

