This shouldn’t be treated as a surprise which it is by most media outlets. The government should audit and review any new technology that can involve public safety. The existence of manual controls is actually irrelevant in the scenario of passengers in the backseat such as Waymo is offering with its unsupervised vehicles right now. There are the traditional controls but if they can’t be accessed, what’s the point?
What might be a valid consideration, is there an emergency stop in the cybercab and how is it accessible? Through the gui on the screen might not be sufficient. I can see a brake pedal not being useful but a quick and readily accessible way to have the car come to a safe emergency stop seems useful.
Tesla and Musk are actually being relatively paced and cautious with the cybercab roll out. Absolutely are not betting Tesla on the deployment and ramp. Some Tesla fans and analysts are getting a head of themselves on the timing. The growth prospects are very real. The actual timing will probably be slower. Even best case scenarios will take years for RoboTaxi revenue to be meaningful.
In our last post, we explained why Tesla is deploying the Cybercab without a special government exemption, relying instead on self-certifying that the vehicle meets all applicable federal safety rules.
That strategy immediately triggers the billion-dollar question: WHAT HAPPENS IF NHTSA DECIDES TESLA’S INTERPRETATION IS DEAD WRONG? 🚨
That possibility is why NHTSA’s fresh Cybercab audit matters so much, and opening the federal rulebook reveals one specific regulation as Tesla’s biggest near-term obstacle.
1⃣ FMVSS 135 could be Tesla’s biggest near-term vulnerability
The Cybercab has no brake pedal, yet FMVSS 135—the federal safety standard governing light-vehicle braking—explicitly mandates that service brakes be activated through a foot control.
While common sense suggests a foot pedal is pointless in a car built without a driver, NHTSA addressed this exact reasoning back in 2020.
Regulators drew a firm line between outdated testing procedures and binding equipment mandates, concluding that an automaker cannot self-certify around an explicit foot-pedal requirement without a formal exemption.
By bypassing an exemption and self-certifying anyway, Tesla is betting its vehicle configuration renders that requirement inapplicable. If NHTSA adheres to its 2020 precedent, Tesla faces a steep uphill battle, with existing regulatory records pointing to roughly an 80% to 90% chance Tesla loses on this specific issue.
While this remains an assessment of regulatory precedent rather than a formal finding against Tesla, it establishes the direct bridge between FMVSS 135 and Part 555. FMVSS 135 creates the potential violation, while Part 555 offers the legal mechanism to deploy noncompliant vehicles.
The path forward splits neatly:
➡️ If Tesla wins the FMVSS 135 argument, self-certification stands and no exemption is required.
➡️ If Tesla loses, the pedal-less design becomes noncompliant, forcing Tesla to modify the vehicle, mount a legal challenge, or pursue a Part 555 exemption to keep cars on the road.
2⃣ That is when the 2,500-vehicle cap gets real
As long as Tesla’s self-certification holds, the Cybercab avoids the statutory volume limits tied to federal exemptions. Once forced into Part 555, however, the commercial exemption pathway generally caps deployment at 2,500 vehicles in any 12-month period.
While 2,500 vehicles works well for an initial pilot, it severely bottlenecks Tesla’s long-term robotaxi vision. Tesla is engineering the Cybercab and its unboxed manufacturing system for mass production, meaning federal caps—not factory capacity—would become the immediate constraint.
This risk is far from theoretical.
Zoox originally attempted to self-certify its purpose-built robotaxi without pedals or a steering wheel, but a subsequent NHTSA audit flagged noncompliances and ultimately pushed Zoox onto an exemption track capped at 2,500 vehicles per year. That precedent proves regulators are fully prepared to steer custom robotaxis into the exemption bucket.
3⃣ Why a 2,500-vehicle ceiling is probably not a permanent dead end
That statutory cap is unlikely to remain a permanent barrier because NHTSA is already rewriting the exact rule causing the problem.
On June 26, the agency proposed modernizing FMVSS 135 for vehicles operated exclusively by an Automated Driving System (ADS), eliminating the foot-pedal mandate and allowing onboard computers to activate brakes directly.
Crucially, NHTSA is not lowering safety standards. The vehicle must still meet identical stopping-distance and braking-performance benchmarks, removing the physical human interface without compromising performance.
In fact, NHTSA noted that physical pedals in a driverless vehicle offer zero safety benefit and could even let passengers inadvertently or intentionally interfere with automated driving.
Because regulators initiated this reform themselves, the question is no longer whether the rule should modernize, but when the rulemaking will be finalized after public comments closed on August 26.
4⃣ A regulatory race between two NHTSA clocks
Because that rulemaking is running alongside the audit, it creates an internal race between two arms of the same agency. NHTSA investigators are auditing Tesla’s current self-certification, while NHTSA rulemakers are finalizing the update that makes the pedal mandate obsolete.
Whichever clock runs out first dictates how disruptive this becomes. An adverse audit determination before the rule is finalized could trigger temporary bottlenecks, emergency exemption filings, or rollout delays. Conversely, if rulemakers finalize the updated standard first, the brake-pedal hurdle evaporates before mass manufacturing begins.
To Tesla’s advantage, NHTSA proposed that the revised rule take effect immediately upon publication, bypassing the typical multi-year phase-in. Based on the regulatory docket, the realistic timeline shapes up as follows:
♦️ ~25% to 35% chance the final rule lands by the end of October 2026
♦️ ~60% to 75% chance it is finalized before the end of 2026
♦️ ~80% to 90% chance it is officially on the books by the end of Q1 2027
The odds that NHTSA ultimately adopts this reform as proposed remain exceptionally high—around 85% to 95%. The core uncertainty is not whether the rule will change, but whether it changes fast enough.
5⃣ The brake pedal might only be the start of the audit
Even a swift modernization of the braking standard does not guarantee clear skies, because the Cybercab also eliminates the steering wheel, accelerator pedal, and traditional side-view mirrors.
NHTSA confirmed that its audit is reviewing Tesla’s broader legal rationale for determining which legacy standards apply to the Cybercab. While the agency is pursuing parallel modernization efforts for mirrors, lighting controls, digital displays, and stability testing, FMVSS 135 is merely the most immediate hurdle. The true scope of any production impact depends on whether investigators challenge those other missing controls.
6⃣ How much could this actually slow the Cybercab ramp?
Balancing these factors, there is roughly a 40% to 60% chance the audit creates a meaningful temporary drag on the pedal-less Cybercab rollout.
Yet the likelihood of the Cybercab remaining trapped under an annual 2,500-vehicle cap long-term is low—likely under 20%. Federal policy is actively shifting to accommodate purpose-built autonomous vehicles, making this a classic timing mismatch rather than a fundamental rejection of driverless design: Tesla brought the vehicle to market before legacy rules finished modernizing.
That mismatch can certainly delay scaling and push volume timelines out, but a temporary administrative bottleneck is vastly different from a permanent ceiling. Tesla backed its vision through self-certification, and NHTSA is auditing that bet against rules written for human drivers while simultaneously rewriting those rules for autonomy.
The entire rollout now hinges on a single question: will NHTSA finish updating the rulebook before its own audit hits the brakes on Tesla’s ramp?