Tesla Begins Rolling Out Update 2026.38.5.1 With FSD v14.3.12 and Halloween Mode

Tesla has started rolling out software update 2026.38.5.1 to its fleet, according to a report from BASENOR - Tesla Accessories. The release bundles together several notable changes, headlined by a new version of the company's Full Self-Driving software, FSD v14.3.12, alongside a seasonal Halloween Mode feature.

FSD v14.3.12 Leads the Release

The centerpiece of the update is FSD v14.3.12, the latest iteration in Tesla's v14.3 branch of its Full Self-Driving software. Tesla typically distributes FSD improvements through these incremental point releases, which arrive bundled inside broader vehicle software updates such as 2026.38.5.1. The report does not detail the specific changes included in v14.3.12, but its inclusion signals continued active development on the v14.3 line.

v14.3 Lite Reaches HW3 Vehicles

Significantly for owners of older vehicles, the update also brings a "v14.3 Lite" build to cars equipped with Hardware 3 (HW3), Tesla's earlier-generation onboard computer. The existence of a dedicated Lite variant suggests Tesla is adapting the v14.3 software to run within the constraints of the older hardware platform, extending at least part of the v14.3 experience to a segment of the fleet that does not have the company's newer computers.

Halloween Mode Adds a Seasonal Touch

Rounding out the release is Halloween Mode, a seasonal addition timed to the October holiday. Tesla has a long-standing practice of shipping lighthearted, themed features alongside its functional software changes, and Halloween Mode continues that tradition in this release. The report did not specify exactly what the mode includes in this version.

As with all Tesla software, update 2026.38.5.1 is being delivered over the air, and rollouts of this kind generally reach the wider fleet in stages rather than all at once. Owners can check their vehicle's software menu or the Tesla mobile app to see when the update becomes available for their car. Further details on the contents of FSD v14.3.12 and the scope of the v14.3 Lite build for HW3 vehicles were not included in the initial report.

Source: BASENOR - Tesla Accessories