The Rebuilt AI Compiler and MLIR-Based Runtime

Tesla's most significant architectural change in the v14.3 line is the complete rewrite of its AI compiler and runtime on top of LLVM's MLIR (Multi-Level Intermediate Representation) . This rewrite was first introduced with FSD v14.3 (software version 2026.2.9.6) and is carried forward in v14.3.5 as a foundation, not a new rewrite in this point release .

The MLIR-based stack delivers a measured 20% faster reaction time on HW4 vehicles and accelerates Tesla's ability to iterate on neural network models, making it a fundamental infrastructure improvement that benefits all driving scenarios .

Upgraded Neural Networks

According to multiple official release notes and changelogs, FSD v14.3.5 includes two neural network upgrades :

• Upgraded Reinforcement Learning (RL) stage — Tesla upgraded the RL training stage of the FSD neural network, resulting in broad improvements across many driving scenarios .
• Upgraded vision neural network — The vision network encoder was upgraded to improve understanding in rare and low-visibility scenarios, strengthen 3D geometry understanding, and expand traffic sign understanding .

These upgrades build on improvements introduced earlier in the v14.3.x series, including better handling of static obstacles, unusual objects, road debris, and animals .

New User-Facing Features

FSD v14.3.5 delivers several new features, some introduced in the broader 2026.20 software branch and others specific to this point release:

• Camera Preview while driving — You can now open the live Camera Preview at any time, not just while parked or during FSD engagement. Go to Controls > Service > Camera Preview, tap any camera view to see it individually, or use the grid button to see all feeds .
• Dashcam Clip Encryption — Dashcam clips saved to a USB drive can now be encrypted. Only your vehicle can view them. To decrypt, tap the padlock icon in the Dashcam app or visit dashcam.tesla.com. Enable/disable via Controls > Safety > Encrypt Dashcam Recordings .
• Parental Controls — You can block Browser, Theater, and Arcade from Controls > Safety > Parental Controls while in Park .
• Actually Smart Summon — Included in this build .
• Blind Spot Warning While Parked — Expanded to the new Model Y, 2021+ Model S, and 2021+ Model X; alerts occupants to approaching cyclists or vehicles before opening doors .
• "Hey Grok" voice assistant — Added to the 2026.20 branch .
• FSD engagement indicator in Tesla app — The Tesla app now displays when FSD is actively engaged while driving .

Driving Behavior Improvements

The release notes for v14.3.x and v14.3.5 directly address several driving behaviors :

• Reduced lane biasing / phantom lane-keeping — Improved handling of lane boundaries and less tendency to steer toward shoulders on repaired roads .
• Reduced tailgating — Improved following distance behavior via the upgraded RL training .
• Emergency vehicle handling — Improved via the upgraded vision network and RL training .
• School bus handling — Part of the general RL and vision upgrades .
• Small animal / unusual object handling — The upgraded vision network targets static obstacles and unusual objects .

What's Working Well: Early Owner Feedback

Early adopters have reported measurable improvements. A v14 review from The Driven found the overall driving experience "noticeably smoother and more relaxing," with speed profiles and better start/end-of-journey behavior enabling over half of trips to be completed without intervention . Early FSD v14.3.2 adopters noted the Standard speed profile is "noticeably better" in 25–45 mph zones and handles 55 mph single-lane highways at 60–62 mph .

Remaining Pain Points

Parking: Still a Major Weakness

Multiple early reviews highlight parking as the most consistent shortcoming. A Teslarati early impressions review from July 14, 2026 states: "Parking attempts on v14.3.5 were not good" — the car parks very far from the destination, especially in large retail plazas . A v14.3.4 test video from July 5, 2026 called destination parking "a major pain point" . Reddit owners on v14.3.3 also found parking worse than prior releases .

Speed Profiles: Inconsistent Behavior

Teslarati's v14.3.5 impressions: "Speed Profiles are still in need of some tweaking; I am adjusting what Speed Profile I'm in frequently, constantly changing it to get it to travel at the correct speed. This was an issue for me on v14.3.4. They're just a little inconsistent" . Reddit users on v14.3.3 reported that "Hurry" mode now drives significantly slower and doesn't overtake slower vehicles as it used to .

Other Reported Issues

• Occasional confusion with darker patches on repaired roads, causing the car to steer onto the shoulder as if avoiding an obstacle .
• Tendency to shift back to the right lane after overtaking, even with a slow-moving semi clearly in view .

Rollout Status (as of July 14, 2026)

• Released July 13, 2026 — Firmware 2026.20.6.6 began pushing to vehicles on that date .
• HW4 (AI4) only — The entire v14.3 branch is exclusive to HW4 vehicles (Model S, 3, X, Y, and Cybertruck with AI4 compute hardware) .
• Limited initial rollout — As of July 14, early adopters confirmed installations, but the rollout is in its first wave and has not reached all HW4 vehicles yet . Broader availability is expected to expand over the following days and weeks.
• HW3 (AI3) vehicles — A separate "FSD v14 Lite" for HW3 began testing in July 2026 but does not include this build .

Bottom line: FSD v14.3.5 is an incremental point release on the v14.3 MLIR foundation. It brings meaningful privacy features (Dashcam encryption, Parental Controls) and an always-available Camera Preview, plus neural network refinements. Early owner impressions are mixed — smoother highway behavior and better speed profiles in some modes, but parking decisiveness and Speed Profile consistency remain notable weak points.

The Rebuilt AI Compiler and MLIR-Based Runtime

Tesla's most significant architectural change in the v14.3 line is the complete rewrite of its AI compiler and runtime on top of LLVM's MLIR (Multi-Level Intermediate Representation) . This rewrite was first introduced with FSD v14.3 (software version 2026.2.9.6) and is carried forward in v14.3.5 as a foundation, not a new rewrite in this point release .

The MLIR-based stack delivers a measured 20% faster reaction time on HW4 vehicles and accelerates Tesla's ability to iterate on neural network models, making it a fundamental infrastructure improvement that benefits all driving scenarios .

Upgraded Neural Networks

According to multiple official release notes and changelogs, FSD v14.3.5 includes two neural network upgrades :

• Upgraded Reinforcement Learning (RL) stage — Tesla upgraded the RL training stage of the FSD neural network, resulting in broad improvements across many driving scenarios .
• Upgraded vision neural network — The vision network encoder was upgraded to improve understanding in rare and low-visibility scenarios, strengthen 3D geometry understanding, and expand traffic sign understanding .

These upgrades build on improvements introduced earlier in the v14.3.x series, including better handling of static obstacles, unusual objects, road debris, and animals .

New User-Facing Features

FSD v14.3.5 delivers several new features, some introduced in the broader 2026.20 software branch and others specific to this point release:

• Camera Preview while driving — You can now open the live Camera Preview at any time, not just while parked or during FSD engagement. Go to Controls > Service > Camera Preview, tap any camera view to see it individually, or use the grid button to see all feeds .
• Dashcam Clip Encryption — Dashcam clips saved to a USB drive can now be encrypted. Only your vehicle can view them. To decrypt, tap the padlock icon in the Dashcam app or visit dashcam.tesla.com. Enable/disable via Controls > Safety > Encrypt Dashcam Recordings .
• Parental Controls — You can block Browser, Theater, and Arcade from Controls > Safety > Parental Controls while in Park .
• Actually Smart Summon — Included in this build .
• Blind Spot Warning While Parked — Expanded to the new Model Y, 2021+ Model S, and 2021+ Model X; alerts occupants to approaching cyclists or vehicles before opening doors .
• "Hey Grok" voice assistant — Added to the 2026.20 branch .
• FSD engagement indicator in Tesla app — The Tesla app now displays when FSD is actively engaged while driving .

Driving Behavior Improvements

The release notes for v14.3.x and v14.3.5 directly address several driving behaviors :

• Reduced lane biasing / phantom lane-keeping — Improved handling of lane boundaries and less tendency to steer toward shoulders on repaired roads .
• Reduced tailgating — Improved following distance behavior via the upgraded RL training .
• Emergency vehicle handling — Improved via the upgraded vision network and RL training .
• School bus handling — Part of the general RL and vision upgrades .
• Small animal / unusual object handling — The upgraded vision network targets static obstacles and unusual objects .

What's Working Well: Early Owner Feedback

Early adopters have reported measurable improvements. A v14 review from The Driven found the overall driving experience "noticeably smoother and more relaxing," with speed profiles and better start/end-of-journey behavior enabling over half of trips to be completed without intervention . Early FSD v14.3.2 adopters noted the Standard speed profile is "noticeably better" in 25–45 mph zones and handles 55 mph single-lane highways at 60–62 mph .

Remaining Pain Points

Parking: Still a Major Weakness

Multiple early reviews highlight parking as the most consistent shortcoming. A Teslarati early impressions review from July 14, 2026 states: "Parking attempts on v14.3.5 were not good" — the car parks very far from the destination, especially in large retail plazas . A v14.3.4 test video from July 5, 2026 called destination parking "a major pain point" . Reddit owners on v14.3.3 also found parking worse than prior releases .

Speed Profiles: Inconsistent Behavior

Teslarati's v14.3.5 impressions: "Speed Profiles are still in need of some tweaking; I am adjusting what Speed Profile I'm in frequently, constantly changing it to get it to travel at the correct speed. This was an issue for me on v14.3.4. They're just a little inconsistent" . Reddit users on v14.3.3 reported that "Hurry" mode now drives significantly slower and doesn't overtake slower vehicles as it used to .

Other Reported Issues

• Occasional confusion with darker patches on repaired roads, causing the car to steer onto the shoulder as if avoiding an obstacle .
• Tendency to shift back to the right lane after overtaking, even with a slow-moving semi clearly in view .

Rollout Status (as of July 14, 2026)

• Released July 13, 2026 — Firmware 2026.20.6.6 began pushing to vehicles on that date .
• HW4 (AI4) only — The entire v14.3 branch is exclusive to HW4 vehicles (Model S, 3, X, Y, and Cybertruck with AI4 compute hardware) .
• Limited initial rollout — As of July 14, early adopters confirmed installations, but the rollout is in its first wave and has not reached all HW4 vehicles yet . Broader availability is expected to expand over the following days and weeks.
• HW3 (AI3) vehicles — A separate "FSD v14 Lite" for HW3 began testing in July 2026 but does not include this build .

Bottom line: FSD v14.3.5 is an incremental point release on the v14.3 MLIR foundation. It brings meaningful privacy features (Dashcam encryption, Parental Controls) and an always-available Camera Preview, plus neural network refinements. Early owner impressions are mixed — smoother highway behavior and better speed profiles in some modes, but parking decisiveness and Speed Profile consistency remain notable weak points.