Legacy Intel Model S and X Are Finally Getting FSD v14.3 Lite — Here's What Owners Should Expect

Owners of older Model S and Model X cars with the Intel Atom infotainment computer have waited through every v14 Lite wave that hit HW3 Model 3 and Model Y. On Tuesday evening Pacific time, that wait started to end. Tesla's Super Intelligence account, @TeslaSI, posted that "FSD Supervised v14 Lite now rolling out to Intel Model S&X." Software tracker Teslascope and at least one owner report put the first installs on the same day.

What was confirmed Tuesday

Teslascope wrote that legacy Model S and X — HW3 Autopilot hardware paired with the older Intel screen computer — received a V14.3 Lite build "for the very first time," calling it the first occasion any such car had gotten a V14 Lite package. Separately, a 2017 Model X owner with the vertical screen posted that the car had started downloading 2026.38.5.1 with FSD v14.3 Lite listed, tagging Teslascope and Not a Tesla App. TeslaSI's short post later framed the same move as an active rollout, not a one-off experiment.

Teslascope's page for 2026.38.5.1, first seen Oct. 13, showed a handful of U.S. installs that day, including HW3 cars. Install counts on early waves are tiny and change quickly, so treat any single-day figure as a snapshot, not a fleet total. Tesla has not published how many Intel S/X cars are in the wave or how long a wide rollout will take.

How this differs from HW3 Model 3 and Y

HW3 Model 3 and Model Y already got FSD (Supervised) v14.3 Lite in the 2026.33.5 and 2026.38.5 lines. Tesla's public release notes for those builds still list Lite for Model 3 and Model Y only. They do not yet name legacy Model S or Model X. Refresh (Ryzen) Model S and X cars are on the HW4 side of the split and get v14.3.12, not Lite.

So for Intel S/X owners, the useful facts today are: community tracking and TeslaSI say Lite is starting to land; the published notes have not caught up; and Tesla has not posted a separate S/X Lite changelog. Until Tesla updates the notes, assume feature behavior matches the published Lite bullets for 3/Y — parking, unparking, reversing, Arrival Options and Speed Profiles, including Sloth — but do not invent S/X-specific claims Tesla has not printed.

HW3 vs. HW4, again

Nothing in Tuesday's reports moves Intel S/X onto the full HW4 v14.3.12 branch. Lite remains the distilled HW3 path Tesla describes as learning from the HW4 v14 model. HW4 cars still get the longer v14.3.12 list, including the rewritten MLIR runtime Tesla says cuts reaction time 20%, plus Automatic Collision Evasion on manual drives. Legacy S/X owners should expect the lighter branch, not feature parity with a 2024–2026 HW4 car.

What it means for owners: if you drive a pre-refresh Model S or X with HW3 and still pay for FSD (Supervised), check Software for 2026.38.5.1 and confirm the FSD version after install. If nothing is offered yet, that is normal this early. Watch Tesla's notes and the car's own release notes screen for an official S/X listing before treating every 3/Y Lite bullet as guaranteed on your car. FSD (Supervised) still requires an attentive driver ready to take over; it does not make the car autonomous.