Automatic Model 3 trunk open/close

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#41
For those of you with this installed - does it have a safety feature that stops the trunk from closing if it senses something blocking it (like the model s trunk)?
 

barjohn

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#42
Yes, it has a pinch stop ability. At the moment I think it takes more force than it should but it will stop if it encounters an obstacle.

On the warranty issue, a nexus must be shown between the installed item and the problem a warranty claim is made on. Under your interpretation, should you have a breakdown of any kind, then anything you do to try and fix the issue could be construed as an unauthorized repair attempt and thus voiding their warranty responsibility. I don't think it works this way.
 

Skione65

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#43
My biggest thing with this would be electrical issues down the road. Due to the fact that you’re tapping into the can-bus and 12v power. What if some sort of electrical issues crop up and they see all this wiring and wire tapping in various and sundry areas? I think they’d be and probably would be compelled to deny you service based on all the wiring modifications. Unless there is a way you could prove your tapping and additions in NO WAY affect the area or issues your we’re in for service for. Electrically I just don’t know how you’d be able to do that.

Ski
 

barjohn

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#44
It would be pretty easy. There are only 3 taps plus power. Two of the taps are CAN bus H and L and one is just to sense the rear trunk hand switch. If you eliminate power to the unit it has no effect and if further proof was needed removing the other three taps is not difficult. As an engineer with many years under my belt I have to admit that it doesn't worry me. It just listens for commands to open or close (it's a toggle so a repeat open is a close). Think of it being like Alexa or Siri. It is listening. When it hears its name (open trunk) it activates the motors on the trunk struts and when it hears its name again it activates the same motors to close the trunk. When you send the open or close command from your phone it goes to the cpu in the car and sends the unlatch command (open). If you press it again it sends it again. On the touch screen it disables the icon (grey it out) after you press it hence you can only open from the touch screen.
 
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#45
There's no greater risk than every stereo installation and/or modification shop on every corner in America. That's why they call carry insurance policies. RPM Tesla, for example, is willing to install an entirely new steering wheel, as stated on their website (which I plan on buying :) ). What is the difference if they are installing a trunk mod and accidentally clip a wire vs. accidentally clipping a wire when they change the steering wheel?

Regardless of the modification, all major car warranties state that if the warranty claim arises out of or relates to the modification, it will be denied.
 

Franklin L

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#46
I just had the power liftgate from TeslaOffer installed.

https://www.teslaoffer.com/product/model-3-power-liftgate-soft-closing/

It’s not cheap, but it’s very slick and everything looks professional down to the buttons you press. I got the add on where making a kicking motion under the bumper opens or closes the trunk. Everything works like a charm and it feels like something that should have been included. Tesla Raj already put up a YouTube video on this— I don’t think I’d have anything extra to show.


The best part for me was that the company owner was doing business in California for a couple weeks and he did the installation on my car. It took him about 2 hours with the tools he bought. As I’m not exactly very handy, this probably would have taken me a couple of days myself. Handy people could probably do it in a day. A pro might need about 5-6 hours to do the first one, according to the company owner, with install times improving with repetition.
 

SoFlaModel3

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#47
Took me 7 hours over the last 2 days. Some mistakes added serious time and the fact that I was filming a YouTube video as well so lots of pausing to frame the shot just right. If I was to do a car from scratch right now without video I would estimate 2-3 hours.

I spent a lot of time with Tesla Raj on Twitter DM and @NateM over the phone helping at places I was stuck.

My video will be a comprehensive install video covering ways to keep the install time down and do it right the first time.

Stay tuned!

 

SoFlaModel3

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#49
As promised, I am following up with the comprehensive installation video!!

 

telero

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#51
As promised, I am following up with the comprehensive installation video!!
Any thoughts on whether the CAN connections on the rear of the center console mentioned by @JWardell and @fast_like_electric in the
Diagnostic Port and Data Access thread could be used? If so, it would be really nice if there was Y-adapter that could be used to get the CAN signals without posi-taps.


In your photo, the large gauge black wire right behind the thick yellow wire is pin 20 (ground). CAN_L is right next to that black wire (pin 19), then CAN_H (pin 18). All of those three wires are on the bottom row of the connector - obscured by the other wires.
 

SoFlaModel3

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#52
Any thoughts on whether the CAN connections on the rear of the center console mentioned by @JWardell and @fast_like_electric in the
Diagnostic Port and Data Access thread could be used? If so, it would be really nice if there was Y-adapter that could be used to get the CAN signals without posi-taps.
Definitely not my area of expertise so I’m not sure on this one.
 
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#53
Any thoughts on whether the CAN connections on the rear of the center console mentioned by @JWardell and @fast_like_electric in the
Diagnostic Port and Data Access thread could be used? If so, it would be really nice if there was Y-adapter that could be used to get the CAN signals without posi-taps.
I believe the answer is yes. They are tapping into the Vehicle CAN bus, which is the same bus that is also at the back of the center console. There's lots of places this goes, but either the left or right body module is likely the shortest wire run as it isn't present in the trunk. You could get it from the center console, but that will add to wire length unless you go under the carpet direct to the trunk / controller.

Be aware you are running a fairly long wire stub at either position, and impacting the signal integrity of the CAN bus by doing this. Unterminated stubs on CAN are generally not wise at high communication speed - should be daisy chained.

But I think the CAN bus connection is the least of the challenges - looks like a complicated install overall. Long term there may also be false indications of bad 12V batteries or other faults as a result of where they are making the power connections. The Model 3 is not like other cars and it looks for unexpected loads on any circuitry besides the 12V accessory power. That topic comes up often with people hard wiring in radar detectors or dashcams - something to watch out for. I'm guessing they went to the battery vs. the accessory outlet due to high inrush or run current of the motor.
 

telero

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#54
I believe the answer is yes. You could get it from the center console, but that will add to wire length unless you go under the carpet direct to the trunk / controller.
Was thinking about going under the seat and under the carpet to not have to run all the way to the front, as well as not having to take so much trim apart or work in as tight of an area in the driver footwell. Total cable run from trunk to back of the console should be a bit shorter than all the way up front.

Be aware you are running a fairly long wire stub at either position, and impacting the signal integrity of the CAN bus by doing this. Unterminated stubs on CAN are generally not wise at high communication speed - should be daisy chained.
Any reason to think this would be any worse than running up front? Quite a lot of people seem to have done that so far without any reported issues.

Long term there may also be false indications of bad 12V batteries or other faults as a result of where they are making the power connections. That topic comes up often with people hard wiring in radar detectors or dashcams - something to watch out for. I'm guessing they went to the battery vs. the accessory outlet due to high inrush or run current of the motor.
Depending on if you want always on or not, that could definitely be an issue. Seems like the idle draw is so low that people that ran direct to the battery haven't had issues (yet?). For me a switched source is fine, so I was planning on the DC-DC converter under the rear seat while running the CAN wires to the console. I definitely wouldn't try connecting power through the harness where the CAN wires are.
 
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#55
Any reason to think this would be any worse than running up front? Quite a lot of people seem to have done that so far without any reported issues.
There will be a level of safety margin designed in, but adding a stub reduces that margin. If the CAN bus was severly affected, yes it wouldn't work at all - due to a phenonen called electrical reflections. In this case you are just imparing the margin, but drive by a strong radio transmitter and have the right messages on the bus and that's where the random issues would manifest.

CAN is robust and fault tolerant by design, but know that you are hooking into the central nervous system of the car - with a device not made to the same standards as the rest of modules on the car. At a minimum I'd always unplug this when doing a firmware update.
 

JWardell

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#56
At 500kbps and jammed with data, CAN can be very finicky, and I have definitely surprised myself adding too long of a stub and screwing up data. You could balance it with a little extra termination maybe. I'm nervous as it is running it up to my dashboard.
If you don't need auto-close though, I think you wouldn't need CAN if the controller can be activated by the factory latch release signal
 
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#57
If you don't need auto-close though, I think you wouldn't need CAN if the controller can be activated by the factory latch release signal
Agree - I'm missing what tapping into the CAN bus is offering - besides hassle and risk. A device like this should be able to look at the factory release signal to open, and you can close with the button that is added in the trunk during the install. Remote closing via the center screen button or app (or fob) seems unnessary for real world use cases - easier to push the close button.

Is the CAN bus connection optional - can the unit work without it?
 

telero

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#58
When I first asked about this I was really just worried about whether the alternate location from the factory install instructions would even work, but now you have me wondering about tapping the CAN at all. There quite of few of these installed with no reported issues that I've seen, but you guys seem to know CAN pretty well and your concerns do make me take pause now.


If you don't need auto-close though, I think you wouldn't need CAN if the controller can be activated by the factory latch release signal
Agree - I'm missing what tapping into the CAN bus is offering - besides hassle and risk. A device like this should be able to look at the factory release signal to open, and you can close with the button that is added in the trunk during the install.

A different company is offering a kit that doesn't tap the CAN wiring. My understanding is that it works by getting the factory latch release signal, and if the trunk is already closed it opens it, or if the trunk is opened it closes it. It also seems to keeps the signal to the car in the trunk closed state so that the on-screen button still works for closing, but always indicates closed even when open. That also seems to bypass a couple safety features like the local button on the trunk or the foot sensor being able to open the trunk while the car is moving, as long as it's under 10 MPH or so.

With CAN monitoring this kit won't open the trunk unless the car thinks it's OK to do so, and it can't be closed from the screen since that button is disabled when opened. Apparently using the app button isn't disabled due to actual state, so pressing it will still get the car to send the CAN signal to open. I guess since the controller knows the state is actually open, it then closes it.



Is the CAN bus connection optional - can the unit work without it?
Don't know about that. Without the CAN connection, I wonder if it would operate like the other kit out there, or if it just wouldn't work. I'm guessing it just wouldn't work.
 
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#59
Perhaps @Tesla Offer can respond regarding what function the CAN bus provides for this, and if it is required for operation. When used with the existing trunk controls (screen/app/fob), the existing hood latch logic in the car is already providing foolproofing so you can't open the trunk while driving. But I could understand that if the foot wave detection feature is used with this accessory, it wouldn't know that the car is in gear to prevent openning. Perhaps the CAN bus connection is not needed if the foot wave detector isn't used.

I imagine the foot wave feature is nice for some people, so in-gear knowledge would be needed. But there should be other ways to deduce this using the ChargePort CAN bus which is in the trunk. Not only closer, but a much less critical bus to hook into. Much different CAN data on that bus, but the collection of info could be used to deduce when the car is in a driving state - and disallow the foot wave. A much better place to hook into vs. way up inside the car, but the system would need to be designed to use the data on that bus.
 

Firewired

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#60
I installed the TeslaOffer trunk and it took like 6 hours, was not easy, really have to know what you are doing. I got my power from the passenger side under the rear seat, making that part much easier. I am very impressed with how communicative and responsive the company is via WhatsApp. They offered me two firmware updates, said if the newer one had issues to install the prior one and it would fix the issues, it did, and they were exactly right. Issues I had upon install were: 1) trunk would not lock with the car, when you would try and open it, alarm would go off, 2) over speed bumps foot sensor would false trigger and open. Teslaoffer had warned me that might be the case on the newer firmware. I installed the prior firmware which uploads via microSD in seconds. The trunk now locks normally with rest of the car, and I have been unable to get the foot sensor to false trigger. I have gone over quite a few speed bumps of various sizes at different speeds forward and backwards, as well as backed up slowly over some low curbs to simulate a foot like movement and nothing. Pretty impressed they could tweak the functionality so much just from firmware.