Tesla began pushing firmware 2026.38.3 to customer cars on 6 October 2026. Its release notes carry seven entries. Six of them have already shipped.
The one that has not is Halloween Mode, and it is the reason the build is being written about everywhere this morning.
What is actually new
| Entry | New in 2026.38.3? |
|---|---|
| Halloween Mode | Yes — first appearance in any build |
| Emergency Drive Away | First shipped in this branch, covered here on 2 October |
| Set Arrival Energy | No — shipped with the 2026.26 Summer Update in August |
| Visual Updates — higher quality vehicle images, enhanced park scene | No — introduced with 2026.38 on 29 September |
| Supercharger Site Maps | No — same branch, same date |
| Dynamic Headlight Leveling | No — same branch, added to the notes on 1 October |
| Security Improvements | Routine |
This is the pattern this site keeps finding in Tesla's release notes: the list describes the build, not the change. An owner reading seven bullets will reasonably assume seven new things. Two of these entries first appeared five weeks ago, and Set Arrival Energy — "set your desired Arrival Energy for any trip from your phone" — has been in cars since August.
Halloween Mode
Tesla's own note is two sentences: "Put a Ghost Costume on your car visualization. Turn on Trick or Treat Mode to play spooky sounds." What has actually shipped is considerably more than that.
- Ghost costume — the car's own avatar on the centre display wears a white sheet with eyes cut out, and it moves when a door opens.
- Parked scene — the backdrop becomes a graveyard with a haunted house, a full moon, jack-o'-lanterns and a hand coming out of the ground.
- Driving visualisation — surrounding cars render green, pedestrians render as skeletons, and the Full Self-Driving path turns purple.
- Trick or Treat Mode — the car plays sounds and flickers its lights when someone approaches, and records the approach the way Sentry Mode does.
- Light show, lock sounds, themed wraps, Boombox voice and a Photobooth makeover — the usual seasonal set.
The constraint is infotainment hardware. The full-screen parked scene needs an AMD Ryzen computer, which leaves out earlier Intel-based Model 3s and Model Ys. Those cars still get the wraps and the lock sounds.
Tesla's framing is that owners can "spread holiday fear year round", which reads as a Toybox entry that stays after October rather than a two-week seasonal unlock — the same way Santa Mode stayed.
Where the rollout is
| Measure | Value |
|---|---|
| First installs | 6 October 2026 |
| Share of tracked fleet | 0.1% |
| Cars updated at first count | about 19 |
| Models listed | Model 3 and Model Y for Halloween Mode; S, 3, X, Y and Cybertruck for the rest of the build |
At 0.1% this is a first-day build and the sample is far too small to say anything about which regions are being seeded. Tesla has not published a market list for Halloween Mode, and none of the three outlets reporting it has one either.
What an owner should do
Nothing. There is no functional change in 2026.38.3 for anyone already on 2026.38 — the parked scene, the site maps and the headlight leveling are the same features they have had since the end of September, and Emergency Drive Away is a US Supercharger feature that damages the charge port by design.
If the ghost is what you want, it will come to the car on its own. If an Intel Model 3 is what you have, the part of it you will see is the wrap and the lock sound.