In early 2023, Tesla launched its FSD Hardware 4.0 – now known as AI4 – an improved version of Hardware 3 with various advantages. This hardware launch initially came off to a rocky start with FSD and Autopilot not being available to freshly delivered vehicles.
Today though, AI4 is the next step as Tesla strides towards full autonomy. While Tesla hasn’t abandoned HW3 or declared it as legacy yet – and doesn’t seem to plan to, it’s still important to be able to figure out what hardware your vehicle has. This is especially true for those who have paid for, or are subscribed to FSD – as it seems that going forward, AI4 will receive major FSD updates before hardware 3, which will require optimization.
So, let’s go over what AI4 offers in terms of improvement, the fact that there is no retrofit path from Hardware 3, and finally, a few easy ways to tell FSD Hardware 3 from Hardware 4/ AI4.
HW4 / AI4 Improvements
AI4 brought along several improvements, including new cameras, new electrical and wiring harnesses, and most of all – improved processing power.
The new cameras bring improved resolution for better details. The rear camera on AI4 has a resolution of 1448x938 vs 1280x960 on Hardware 3. However, there’s a much larger differences in the front cameras. HW4/AI4 has a resolution of 2896x1876 while HW3 has a resolution of 1280x960. That’s a huge improvement in quality - additionally, that telltale red tint that they have ensures better performance in low-light conditions. The video below compares the difference between HW3 vs HW4.
Musk previously said that HW4 is about 3-5x faster than hardware 3, although all of that compute power isn’t being utilized yet. We’ll likely see the full power of HW4 come into play with the divergence of HW4 later this year.
How to Tell If You Have HW3 or HW4 / AI4
Not a Tesla App
If you have access to the inside of the vehicle, the easiest and surefire way of determining the FSD hardware of a Tesla is to check in settings. As of software update 2024.38, Tesla has added the ability to view the vehicle’s hardware version. To see simply go to Settings > Software and then tap Additional Vehicle Information.
In the list of options, you’ll see ‘Autopilot computer’, followed by the FSD computer hardware version. You’ll likely see version 2.5, 3 or 4.
If You Don’t Have Access to the Vehicle
Note the telltale red glint of the HW4 cameras
Not a Tesla App
You should still be able to tell what version of the FSD computer is in the vehicle even if you don’t have access to the inside of the car. There are a few several ways to tell if you have Hardware 3, or HW4.
Delivery Date
The first is based on your model and delivery date. If you purchased Model S or X, you’ll likely have AI4 if you purchased after March 2023. If you have a Model Y, it’s after late May 2023 for vehicles made in the United States. The updated 2024 Model 3 has HW4, but if you have a 2017-2023 Model 3, you’ll have Hardware 3.
Red Camera Lenses
Next, if you’re not sure of the delivery date of your vehicle, or want to confirm, take a look at the vehicle itself. HW4/AI4 has cameras with red lenses – the easiest place to see this is on the front cameras – where there will be 2 red lenses and one black (fake) lens. AI4 got rid of the 3rd front-facing camera since the cameras now have a higher resolution.
The repeater cameras are also slightly different, with the same red tint, but include a smaller and narrower turn indicator.
HW4 (top) and HW3 (bottom) repeater cameras
Not a Tesla App
No Retrofit to HW4
Elon Musk and Tesla have confirmed that unlike AP 2.5 or AP 2, Tesla does not intend to offer a retrofit for older vehicles. This isn’t a surprising move, especially given the fact that there is an entirely new wiring and cooling harness for the compute unit in AI4.
This, in turn, with AI4’s different form factor, means that upgrading HW3 vehicles to AI4 isn't feasible. A retrofit would be a complex and expensive task that would likely require building a custom solution that would fit into HW3 vehicles. It also comes with other complications, such as overwhelming Tesla Service. Instead, Tesla will continue to do it the software way – by optimizing and updating the FSD models to perform well on Hardware 3.
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Last week, Mark Ruber, an engineering YouTuber best known for his glitter bombs, released a video where he tested Tesla's Autopilot against various conditions - including the iconic ACME painted wall.
During this test, many people noted that Mark was using Autopilot rather than FSD, even though his video was titled “Can you Fool a Self-Driving Car?”. The Tesla on Autopilot went up against a vehicle equipped with Luminar’s LIDAR rig, running some sort of basic autonomy or safety software.
New Video Tests FSD
Many people were disappointed with Mark’s video and his testing methods, so several creators got to work to actually test out Tesla’s FSD.
Creator Kyle Paul over on X made a much better follow-up video, using both a HW3 Model Y as well as an AI4 Cybertruck. In a relatively unsurprising turn of events, the Cybertruck was successfully able to detect the wall, slowed down, and came to a stop. The Cybertruck was running FSD 13.2.8.
Kyle’s team did a fantastic job building the wall and testing this in a private area using FSD rather than Autopilot. On top of that - they re-tested the results several times and recorded the entire thing in and out. While Mark’s video was more for entertainment, Kyle really set out to prove what would really happen in this unlikely scenario.
Sadly, the HW3 Model Y was unable to detect the wall, and manual intervention was required in each test. While the Model Y was running FSD 12.5.4.2 rather than an FSD V12.6 build, we don’t expect this to have had a significant impact on the test - this is more of an issue with how computer vision analyzes the environment.
There are several major differences between HW3 and HW4. The first is obviously that the version that runs on AI4 is more advanced, as the hardware is capable of processing a lot more data. However, AI4 also features much higher-resolution cameras than HW3, and Tesla recently added the ability for the video feeds to be processed at full resolution on FSD V13. This could have made the difference, although it’s not entirely clear. Perhaps if HW3 gets a version of FSD V13 in the future, HW3 can be retested to see if it passes the “ACME wall” test.
Watch
Kyle’s entire video is below. It’s only 10 minutes long, so definitely give it a watch. Props to Kyle on the quick and thorough execution.
What Does This Mean for FSD?
We broke down Mark’s test - and examined all the little issues that we discovered after doing some in-depth research - you can read our analysis here.
Putting aside the issues with Mark’s testing and instead using the new results - it seems that if you were to have to fight against Wile-E-Coyote and his ACME tools with your Tesla, cartoon logic may win if you’re on an HW3 vehicle. If you’re on an AI4 vehicle, you’ll likely come to a safe stop.
Vehicle depth perception is definitely something that Tesla has been hard at work to improve - and some fairly drastic improvements came with FSD V13 that haven’t been entirely translated to FSD V12 just yet. Future versions of HW3 FSD may be able to determine that the wall is there successfully. So Kyle - if you’re reading this - don’t get rid of that wall. We’d love to see more testing in the future.
However, this entire test scenario is so out of left field… there is a good likelihood this same test would fool some human drivers as well. The most important part is that the future of autonomy will not fall for these tricks, so it's very unlikely for someone to weaponize this idea as it’d only possibly work on a small segment of vehicles.
If Wile-E-Coyote is after you, someone else may drive into the wall before your Tesla does.
Not a Tesla App
We’re not kidding, this really happened already. This isn’t a realistic scenario outside of someone trying to play an insane prank - but it’s good to know that FSD V13 is capable of dodging this.
Tesla regularly holds quarterly all-hands meetings for employees, but last night marks the first time Tesla has live-streamed the event for the public.
The meeting primarily focused on Tesla’s employees, recent achievements, and the future of Tesla. While it didn’t reveal much new information, it was interesting to see Elon Musk candidly engaging with his teams, who seem to genuinely enjoy working with him. Still, there were a few noteworthy takeaways.
As with Tesla’s Earnings Calls and other live events, we’ve put together a concise, easy-to-digest recap of everything discussed.
General Points
Work-related Injuries declined over time
Planning to expand to new markets
Cell Manufacturing
Continuing to invest in battery supply
Cheapest, lowest cost per kWh cell
The supercharger network continues to grow
Vehicle range and charging speed should match the needs of humans and their required time for breaks
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