Driving behind a Model S

Driving behind a Model S

Today I was pleasantly greeted by a MS just like mine. It passed me up and continued on our way down the freeway. The speed was consistent with moderate traffic. I followed it for five or so miles. What I noticed was how often the brake lights came on. I think the regen. deceleration brake lights is too sensitive. It was like somebody resting their foot on the brake pedal. I hope my brake lights aren't that active. It may be a driving habit but how do you know?

David Trushin | 17 October 2013

Sounds like a newbie who hasn't gotten used the regen yet.

jat | 17 October 2013

I agree, but it is also tricky about wanting to make sure that you show the brake lights when the car is slowing down. Personally, I think you could do something smarter with it to make it behave more like a driver in an ICE would be showing the brake lights.

jeremythehunt | 17 October 2013

What freeway did this happen to be on?

Koz | 17 October 2013

You can tap the Tesla icon at the top of the screen to bring up info on your car, including the software rev. The image of your car on the screen in this screen is "active" and will show when your brake lights come on. From my experience, it is set properly. At least in my vehicle.

Andercam | 17 October 2013

The driver you were following was lifting too far off the go pedal. When I got my car, I watched the graphic closely because I didn't want my brake lights to come on too often. You can lift lightly that will slow the car some without the brake lights coming on, but it's not enough to worry about somebody driving into the back of you.

FYI - tapping on the Telsa logo in v5 brings up an image of the car, but won't show the lights. If you click on the "charging" button, the lights will show in there.

Prasad B | 17 October 2013

Fordy, was this on 101 North in the Bay Area, and was yours a gray Model S following a black one?

Car t man | 17 October 2013

Tesla should utilize a multi stage third brake light. Only the third braking light should come on with regen and in stages, where the number of lit up diodes grows proportionally to level of regen used. So more leds shine up
when regen is stronger and less when it is milder. It is way more informative for the driver in the car that follows.

It wouldn't be a meaningful hardware cost increase but it likely is patented. Considering that this is somewhat of an annoyance and even safety factor, I think it is worth at least exploring for Tesla.

Chuck Lusin | 18 October 2013

@Car t man

Good idea, but no one other than Tesla owners will have a clue what the different stages mean.

Cattledog | 18 October 2013

This isn't for everyone, but I typically set my regen to low when on the freeway. I do not believe it triggers the brake lights even when lifting completely off the accelerator. Feels more like ICE auto transmission too - more glide.

Brian H | 18 October 2013

I think it's intuitive enough. Seeing it for about 5-10 seconds would be enough.

Thomas N. | 18 October 2013

I don't really care if my brake lights come on a lot. If another driver doesn't like it and thinks I'm riding the brakes well then he has the option of passing me or hanging way back.

I'd be more concerned if my brake lights were NOT coming on. Then I stand a chance of getting rear-ended and that would ruin my day. I know because it's happened to me 3 times over the years driving here in Los Angeles. Maybe that has something to do with my tolerance/support of the Model S lights coming on during hard regen.

Kaboom | 18 October 2013

Differing levels of brake light effects or intensity is needed. There is a big difference between some mild regenerative braking, and someone hitting the actual brakes full on.

For the person behind me, and the safety of people in my car, i want them to be able to tell the difference.

Its like the boy who cried wolf if MS keeps flashing full brakes all the time whenever you just depress the gas, the trailers will get desensitized and wont give proper respect to a full hard brake

Fordy | 18 October 2013

This was north of Seattle. Watching the image is a good idea. I really just want to see for myself how they work.

Andercam | 18 October 2013

Kaboom +1

Its like the boy who cried wolf if MS keeps flashing full brakes all the time whenever you just depress the gas, the trailers will get desensitized and wont give proper respect to a full hard brake

Carefree | 18 October 2013

I was initially concerned about the regen brake lights coming on all the time. Having owned the car for 7 months now it really is NOT an issue. As long as you don't take your foot completely of the accelerator your brake lights don't have to come on.

I don't think this is any different than dealing with ICE drivers. Some have a "nervous driving style" eg. they keep hitting the brakes without any obvious reason (hate those drivers) and I guess some Model S drivers constantly take their foot completely off the accelerator.

MacDaddyDude | 18 October 2013

Kaboom +2

The last thing I want to do is "teach" tailgaters that those flashing break lights don't mean anything...just ignore them.

Vicelike | 18 October 2013

You can see your brake lights at night in the rear view camera lighting change. They come on when the regen is creating the same decelleration as lightly breaking on my Toyota.

If you don't learn to use the accelerator properly you are the equivalent of some drivers who are always either on the gas or the brake in an ICE car.

Not a good thing for the car, the passengers or those who are following.

hubertz | 18 October 2013

The image of my car when I tap the Tesla icon is the drivers side view. Can this be changed to see the rear of the car and hence brake lights. If not how do you see the brake lights during regen?

Andercam | 18 October 2013

You will be able to see the brake light(s) from the side view.

Eletrek | 18 October 2013

It was reported elsewhere that brake light only come on when regen (green line) hits 30kw. This seems about right based on my experience.

danej | 18 October 2013

It's frustrating to have to "feather" the throttle in hopes of avoiding panicking the folks following. I've been flipped off by folks who thought I was intentionally "brake checking" them when I simply let off the gas for a moment.

It's unrealistic to expect Tesla drivers to learn some new way of driving, so as a class of vehicle we end up looking like we are constantly tapping our brakes. It may be a necessary evil though because we ARE slowing at this point.

Makes me wonder, does a diesel which has similar "drag" when you let off the accelerator due to engine compression also light it's brake lights? I'd guess not. Wonder if diesel drivers get rear-ended more frequently.

I'll try the trick of changing regen to "low" when on the freeway and see how that feels. (Can you change regen settings while in motion?)


AmpedRealtor | 18 October 2013

I like standard regen in most instances, but I dislike it at freeway speeds when disengaging the cruise control. I wish Tesla could modulate the regen after turning off the cruise control to prevent the immediate and dramatic slowdown that occurs afterward. It would be nice if there was a way to have it automatically use the low regen setting when disengaging the cruise control, but keep it as standard in other situations.

Carefree | 18 October 2013

The slow-down effect of diesel trucks or cars when letting off the gas pedal is nowhere near as dramatic as the regen on the Model S. There is no need for brake lights to come on.

Andercam | 18 October 2013

I have found as a general rule... if you let off the go pedal, and your body moves forward, the brake lights come on. If you ease off the pedal, and you don't feel your body moving forward, the brake lights won't come on.
You can't base if off the amount of regen on the display.

jbunn | 18 October 2013


I have the same observation about disengaging cruse control smoothly. It's hard to get out of it smoothly. Best I can come up with is to have my foot on the "prissy" pedal about where I think it should be, then use the stalk switch to turn off cruise.
Not all that easy to do it without giving the passengers shaken baby syndrome.

I'm not worried about my brake lights on the freeway, though. If I'm doing 70, and my brake lights startle the person behind me they are TOO close anyway.

Brian H | 18 October 2013

CC: accelerate slightly faster than its setting, then disengage.

AmpedRealtor | 18 October 2013

@ Brian H - Great idea, duh why didn't I think of that?

Superliner | 18 October 2013

"Off Topic" (sortof) I WISH the brake lights came on in my Volt during regen, when one pedal driving my volt in traffic (gear position "L" for "max" regen. the slow down is rather dramatic and there are no brake lights

mrspaghetti | 18 October 2013


"It's unrealistic to expect Tesla drivers to learn some new way of driving"

Why is it unrealistic? Everyone used to drive a stick, now almost no one does. Before that they rode in wagons, etc. The vehicle operates fundamentally differently, adjustment is required. IMO this is not a radical adjustment either.

Thomas N. | 18 October 2013

Ever drive a Porsche 911 with a manual transmission? That is unlike any other car I had ever driven. I had to completely adjust my driving style to make that car work. And I liked it!

Roamer@AZ USA | 18 October 2013

@AmpedRealtor. My BMW has active cruise. It was great training for the Tesla cruise. Every time a car cuts close in front I have to get on the gas pedal fast and match the speed before the auto cruise freaks out and hits the brakes. I would over ride the auto cruise while I eased back to the distance I had set for follow.

I guess years of driving auto cruise made it instinctive to match the accelerator pedal to the cruise set point. I usually press until I feel it go just above set point.

Roamer@AZ USA | 18 October 2013

I found out my wife was worried that the brake lights didn't come on during regen so she was riding the brake to avoid getting hit from behind.

Solved it by turning on the camera at night so she could see exactly when they came on and went off on accelerator movement. Only required a little driving time for her to trust that they were coming on when they should. We grew up on stick shifts so it was natural for her to assume you didn't get brake lights unless you pushed the brakes.

The camera at night is nice because you see it with peripheral vision and don't need to look down.

gregv64 | 19 October 2013

Just to agree with other people that the break lights come on when the should, ie during hard deceleration. The fact is, that for the original poster the person in the car in front of you was doing the Tesla equivalent of riding the brake, they were taking their foot entirely off the accelerator and thus braking hard every time they wanted to slow a little. It's just as bad and annoying as somebody riding the brake in an ICE. On the freeway regen has to be above 30kW to activate the brake lights, and there's zero reason to brake that hard unless the person in front of you is braking.