The FMVSS 135 Proposal for Vehicles Without Manual Controls
Published
Proposed rule; comment period closed July 27, 2026. Law checked through October 18, 2026.
Since the first wagon, the means of stopping has rested in the driver's hand or foot. The reins, the hand brake, and the pedal assumed a person in the seat. Federal Motor Vehicle Safety Standard No. 135, which governs light-vehicle brakes, still makes that assumption, and a vehicle with no driver's seat cannot meet it as written.
On June 26, 2026, NHTSA proposed to change that (91 FR 38593, Docket NHTSA-2026-0728). The foot-operated service brake and the parking brake control requirements would apply only to vehicles with manually operated driving controls. For vehicles without them, the proposal defines a "service brake control" activated by onboard systems rather than an external command, and replaces pedal-force test inputs with a manufacturer-specified control input. Stopping-distance requirements would not change. The brake warning indicator would become a "telltale" visible from every designated seating position in a vehicle without manual controls. The parking brake would no longer need to be a friction type, but it would still have to hold the vehicle on a 20 percent grade by mechanical means. NHTSA expressly took no position on how a passenger should be able to tell an automated vehicle to stop.
The proposal is one of a set. NHTSA also proposed in 2026 to adapt Standards No. 102 (91 FR 12532), Nos. 103 and 104 (91 FR 12537), and No. 110 (91 FR 16172) for vehicles without manual driving controls.
Texas requires an automated vehicle's driving system to comply with the federal standards. Until these proposals are final, a vehicle built without a pedal must reach Texas roads through a federal exemption or a defensible certification; the questions NHTSA put to Tesla in AQ26002 show what that defense must answer.
Limits
Current FMVSS No. 135 applies until a final rule takes effect. The proposal addresses brake hardware and testing, not whether an automated system brakes appropriately in a given situation.
Sources
- NHTSA, 91 FR 38593 (June 26, 2026)
- 91 FR 12532
- 91 FR 12537
- 91 FR 16172
- 49 C.F.R. § 571.135
- Tex. Transp. Code § 545.455