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Winter Quirks with Tesla’s Cruise Control System

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I use cruise control a lot when driving. Highways, back roads, you name it. My main motive for using cruise control as much as I do is to avoid the urge to speed. After all, it’s far too easy to speed in the Model S with its smooth instant acceleration and lack of engine noise.

I did a fairly detailed review of the Model cruise control system back in the spring of 2014 but it turns out there’s more to the story than I originally thought. The frigid New England temperatures have affected battery range and the ability to use regenerative braking but little did I know that it would also affect the cruise control system.

Model S Cruise Control and Cold Weather

Cruise control is designed to maintain a constant speed without having to use the accelerator pedal. On level terrain it’s pretty reliable in terms of keeping a constant speed, but results begin to vary when going downhill with cruise control on.

In most ICE cars, cruise control will not apply the brakes but will leave the car in gear allowing the vacuum of the engine and engine braking to slow the car down. Some cars will also downshift to further increase engine braking as a means of slowing the vehicle.

The Model S on the other hand has no engine or transmission that can be used for engine braking. Because of this the Model S cruise control system relies strictly on the effects of regenerative braking to slow the car down. When regenerative braking is limited, the rate in which the vehicle decelerates is also limited which in turn limits the ability for the vehicle to automatically slow down.

Unlimited Cruise

Tesla Model S cruise control ineffective when regenerative braking is limited due to cold weather conditions.

In the image above, I had cruise control set at 40MPH but because of the limited regenerative braking due to cold weather combined with a down hill decent, the Model S ended up plowing right past the 40 MPH mark as gravity took hold of the car. I ended up speeding 13 MPH over the cruise control  speed.

Model S owners get to choose between standard and low regenerative braking but it doesn’t make that much of a difference during cold weather conditions since regen as a whole will be limited.

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There is Tesla Life Outside of California

Some California Tesla friends were surprised that I was concerned about this winter quirk. Their thought was that the Model S would operate normally after a short warm up period and this issue shouldn’t be considered a big deal. They suggested I accelerate hard a few times to get the vehicle back to “normal” temperatures but that’s easier said than done when you’re dealing with winter road conditions.

Tesla-Model-S-winter-snow

Warming 7,000 battery cells up to optimal operating temperatures takes time. Here in New England with temperatures well below the 40’s, it often takes 45 minutes of highway driving before regen kicks back in and can accept over 30kW. But more often than not I’m driving without regenerative braking because of the cold weather.

30kW of regenerative braking is needed for slowing the car down. Anything less and the car begins to gain speed as it begins to roll downhill. How fast it gains speed really depends on how limited the regen is.

If you live in colder climates and use cruise control on your Model S, beware of this winter quirk or run the risk of picking up a hefty speeding ticket.

"Rob's passion is technology and gadgets. An engineer by profession and an executive and founder at several high tech startups Rob has a unique view on technology and some strong opinions. When he's not writing about Tesla

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Elon Musk drops a Thanksgiving hint about Starship’s biggest test yet

Elon Musk says Starship Flight 15 will try to catch the ship itself, a first.

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Elon Musk says SpaceX’s next Starship flight will try something nobody has done before, by catching the ship itself. Speaking to roughly 2,000 people at the X Takeover event at Giga Texas on Saturday, Musk said Flight 15 is about four to six weeks away and “probably launches a little bit before Thanksgiving, is my guess.”

That is a slip from earlier reporting, which had pointed to a launch as early as October 19. Musk explained why the date keeps moving. “We’re making a bunch of improvements to the rocket between every flight,” he said, adding that there are often hundreds, sometimes thousands, of small changes. This time the list is short, “but some of them take a fair bit of work and we’ve got to go inside the tank to make some of these changes.”

“We’re going to try to catch the ship, which is a super big deal,” Musk said. “If we do so, that’ll be the first time that there’s been full recovery of an orbital class rocket.” SpaceX has already caught the Super Heavy booster with the tower’s mechanical arms, and has talked about catching the ship since late 2025, but the upper stage has never been caught.

Musk also laid out what comes after. “The next big milestone would be to refly both the booster and the ship,” he said, describing a Flight 16 where “all parts of an orbital rocket are reflown.”

The reason SpaceX wants this comes down to cost and cadence. Every Starship ship so far has ended its flight in the ocean, and SpaceX expects most of those water landings to end in fireballs. A ship that returns to Starbase intact can be inspected and flown again. SpaceX’s IPO filing, says Starship V3 is designed to deliver 100 metric tons to orbit in a fully reusable configuration, that SpaceX aims to cut the cost to reach orbit by 99% or more versus the historical average, and that tower catches should allow “multiple launches per day.”

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The payoff goes beyond cheaper launches. The next generation Starlink V3 satellites are too large for Falcon 9 and can only fly on Starship, which can carry up to 60 per flight. Flight 14 on September 28 deployed the first 26 of them after Starship reached orbit despite an early engine shutdown, as Teslarati reported. Musk blamed engine computer software, and said the heat shield “was extremely robust,” which he claimed in August had solved Starship’s biggest challenge.

NASA’s Moon plans depend on the same capability. NASA’s inspector general has described a lander mission that needs a propellant depot in low Earth orbit and more than 10 tanker flights, with SpaceX targeting one tanker launch every six days. That schedule only works if ships and boosters come back fast and fly again. Also, ship to ship propellant transfer has not been attempted yet.

One interesting hurdle yet to be explored is bringing the ship back to the launch site, with reentry over land, which will undoubtedly come with a lot of aviation safety reviews.

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Tesla’s mirrorless Cybercab will give riders a visibility upgrade

Tesla engineer confirms Cybercab update letting riders pull up rear and repeater cameras on demand.

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Tesla Cybercab camera visibility for passengers (Credit: Dan Burkland via X)
Tesla Cybercab camera visibility for passengers (Credit: Dan Burkland via X)

Tesla is working on a Cybercab update that would let passengers pull up the vehicle’s rear and side cameras on demand, and the request came straight from a rider.

The exchange played out on X late Friday. Cybercab rider Dan Burkland shared photos of the two-seater’s cabin screen after an evening ride, praised the UI team’s work, and left one request: let riders open the rear and repeater cameras whenever they want, “especially for peace of mind.” Tesla UI software engineer Evan (@CarCoder) answered with two words: “In development.”

The idea fits a pattern Teslarati has tracked since public rides began. Days after paid Cybercab service opened in Austin, Tesla sent riders a survey that asked them to rate the touchscreen, the app and the cabin, and to pick the features they wanted most. We reported on that survey in September, and a camera view is the kind of small software change Tesla can push quickly if riders keep asking.

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It also speaks to something unique about the vehicle. With no steering wheel, no pedals and no driver, passengers have no mirror to check and no way to see behind them. The hardware is clearly built for camera awareness, from the repeater cameras to the rear camera. Letting a passenger look through those same cameras would give a nervous first time rider a way to confirm what is around the car.

The timing matters because the fleet is growing fast. Tesla’s Robotaxi account said on Saturday that more than 300 Cybercabs are now serving Austin, an eightfold increase in 30 days, and Tesla AI chief Ashok Elluswamy named Dallas as the next city. More cars and more cities mean more people riding in a driverless vehicle for the first time, which is exactly when small trust features carry weight.

For now, the feature is confirmed only as in development. If Tesla follows its usual pattern with Cybercab software, riders could see it appear in a point release without any announcement, and Teslarati will watch for it.

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Tesla’s Cybercab fleet jumped 8x in a month, with Dallas up next

Tesla confirms its first official Cybercab fleet number as Austin scales fast and Dallas looms.

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Tesla says more than 300 Cybercabs are now serving Austin, the first time the company has put an official number on its active Cybercab fleet. The figure came from the Robotaxi account on X on Saturday, which wrote that one month after launch the service had “scaled to 300+ Cybercabs serving Austin – an 8x increase in 30 days.”

Ashok Elluswamy, Tesla’s head of AI software, quoted the post with a line that carried the bigger news. “Two years since the 10/10 Cybercab WeRobot event, the cabs are everywhere in Austin now. Dallas soon,” he wrote. It is the first time Tesla has named the next city for public Cybercab rides.

Tesla opened Cybercab rides to the public in Austin on September 4, as Teslarati reported, a day after an invite only launch event. The ramp since then has been steep. Our September 28 report had the fleet at well over 100 units after availability jumped from 58 to 125 in a single week. On Thursday, Tesla added 150 Cybercabs to the Texas automated vehicle registry, lifting its registered count to 319 from 169. The first seven appeared on the registry on August 31.

RobotaxiTracker, a community site that counts vehicles from sightings and state records, listed 275 vehicles in unsupervised service in Austin on Saturday, 105 of them Cybercabs, which is well below Tesla’s figure. Tracker counts can lag official numbers, though Sawyer Merritt noted that Cybercab wait times in Austin stayed short on Saturday evening even with more than 2,000 fans in town for X Takeover.

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Regulators are watching the rollout. NHTSA opened an audit query into Tesla’s certification that the Cybercab meets federal safety standards, and sworn answers are due October 30. Tesla reports third quarter earnings on October 21, which gives the company a natural venue to define its fleet numbers and put a date on Dallas.

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