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They do on my Renault Austral.
Current: MY24 Renault Austral Iconic FHD.
Ordered 5/2/26: Chery Tiggo 8
Previous Motability cars:
2013 Ford Focus estate auto.
2016 Vauxhal Zafira 1.4T SE Auto.
2019 Ford Kuga Vignale 1.5 auto AWD. (Ext lease)Yes, if you slow above a set rate, they are required to trigger the brake lights. Effectively anything stronger than engine braking needs to be treated like using a physical brakes.
I'm Autistic, if I say something you find offensive, please let me know, I can guarantee it was unintentional.
I'll try to give my honest opinion but am always open to learning.Mark
Regenerative braking is governed by the law that requires any deceleration of 1.3 metres per second squared, or greater, to activate the brake lights. This regulation applies to all types of regenerative braking, including those that occur when the driver lifts off the accelerator pedal or presses the brake pedal.
Manufacturers can also allow their cars to generate a braking signal for gentler regenerative braking forces than this, but it is not mandatory. DOT guidance inc (Regulation ECE R13H)If you are slowing down at all, the brake lights come on during regen.
Just like a brake pedal, as soon as it moves, the brake light switch activates when the pedal is pressed.
Recuperation braking do you mean regeneration braking.. YOU SHOULD NOT BE USING THIS AS A MEANS OF EMERGENCY OR NORMAL BRAKING THIS IS TO RECHARGE YOUR BATTERY AS YOU SLOW DOWN THAT’S WHY THE BRAKE LIGHTS COME ON BECAUSE IT DOES SLOW DOWN QUICKER.. THIS IS DANGEROUS DRIVING AND MUST STOP.. IF YOU ARE UNSURE ASK GOOGLE…..
YES THE LIGHTS COME ON BUT
1. The Power Limit
Regenerative braking is limited by how much energy the battery and motor can handle at once. If the battery is nearly full, or if the motor hits its peak “recharge” rate, the braking force plateaus. Your physical brake pads, however, are designed to convert massive amounts of kinetic energy into heat instantly.
2. Speed and Physics
Regen braking is most effective at moderate speeds. As you get very slow (approaching a full stop), the motor’s ability to generate resistance drops significantly. In an emergency, you need maximum stopping power all the way down to 0 mph, which only the friction brakes can reliably provide.
3. Consistency and ABS
In a panic, you need the vehicle’s Anti-lock Braking System (ABS) to take over. ABS is intricately tuned to the hydraulic brake system. If you try to modulate your speed only through regen during a slide or on a slick patch, the computer might not react as quickly or effectively as it would if you just smashed the brake pedal and let the ABS hardware do its job.
4. Reaction Time
Most EV and hybrid systems have a slight “ramp-up” for regen to keep the ride smooth. In an emergency, you don’t want smooth; you want immediate. Moving your foot to the brake pedal sends a clear, high-pressure signal to the calipers to bite now.
Yikes! Easy with the shouting.
I always use the brake pedal, for extra control. Although it has to be said that the emergency braking system in my car once responded fractionally quicker than I did, and the brake pedal was already depressed when I got to it. Even when the car is slowing itself ‘cos I’m decelerating e.g. for a junction, my foot is hovering over the pedal to apply more pressure when it’s needed.
The question was whether the lights come on, nobody mentioned relying on the system for normal braking.
Current: MY24 Renault Austral Iconic FHD.
Ordered 5/2/26: Chery Tiggo 8
Previous Motability cars:
2013 Ford Focus estate auto.
2016 Vauxhal Zafira 1.4T SE Auto.
2019 Ford Kuga Vignale 1.5 auto AWD. (Ext lease)Recuperation braking do you mean regeneration braking.. YOU SHOULD NOT BE USING THIS AS A MEANS OF EMERGENCY OR NORMAL BRAKING THIS IS TO RECHARGE YOUR BATTERY AS YOU SLOW DOWN THAT’S WHY THE BRAKE LIGHTS COME ON BECAUSE IT DOES SLOW DOWN QUICKER.. THIS IS DANGEROUS DRIVING AND MUST STOP.. IF YOU ARE UNSURE ASK GOOGLE…..
I don’t know if you already have an electric vehicle, but you may benefit from further driving coaching if you think the above nonsense.
Disregarding emergency braking which is different entirely, regen braking is the smoothest most efficient way of driving an electric car. Some people find they struggle to adapt to it or don’t like it
I’ve been an Advanced Driver for 40 years so driving smoothly was kind of instilled in me.
My BMW i4 has a setting called Adaptive Regenerative Braking and in 90% of driving conditions it’s perfect for slowing down for junctions, roundabouts, hazards and traffic ahead. Yes the brake lights come on as said above.
If you’re skilled with the controls, you can moderate the regenerative braking simply by easing off the throttle, but not completely relaxing it. There’s a lot of driving satisfaction and pleasure to be gained by doing this.
However, if you’re not interested in driving and just want to get jerkily from A to B, switch off regen and keep prodding that brake pedal!
2024 - BMW i4 Grand Coupe eDrive 35 Sport
2020 - Volvo XC40 T4 Inscription
2017 - Audi Q3 TFSi Sport S-TronicAI gone mad, I do wish people would look up regulations without SHOUTING AI!
“The regulation ECE R13H (as my previous comment) mandates that if the rate of deceleration reaches a specific threshold, the vehicle must signal its intent to slow down. This threshold is typically set at a rate of deceleration equivalent to light conventional braking, often around [latex]1.3 meters per second squared (m/s^2) [/latex], which is approximately [latex]0.13 g [/latex] of force. If the regenerative braking force alone causes the car to slow down at or above this intensity, the brake lights must turn on. This regulation ensures that the energy-saving benefits of regeneration do not compromise established road safety protocols.”
Approval E11-13HR012439
The above approval mark affixed to a vehicle shows that the vehicle type concerned has, with regard to braking, been
approved in the United Kingdom (E 11) pursuant to UN Regulation No 13-H under approval number 012439. The first
two digits of the approval number indicate that the approval was granted in accordance with the requirements of the
01 series of amendments to UN Regulation No 13-H.Wow, some nonsense has appeared.
Speaking as someone who drives around town without touching the brake pedal, I can safely say that if you can drive properly and have awareness of your surroundings, you’ll rarely need to brake faster than regen can provide (depending upon just how effective it is in your car). Mitch will have all he needs in the KIA as it has the same system as my Ioniq 5.
I'm Autistic, if I say something you find offensive, please let me know, I can guarantee it was unintentional.
I'll try to give my honest opinion but am always open to learning.Mark
@Joejo
Above is buried in here and also aligns with my first comment
https://eur-lex.europa.eu/legal-content/EN/TXT/PDF/?uri=CELEX:42023X0401
@Joejo Above is buried in here and also aligns with my first comment https://eur-lex.europa.eu/legal-content/EN/TXT/PDF/?uri=CELEX:42023X0401
I was sure the break lights would come on if the car slowed down significantly. 👍
I used so little of the normal brakes that in the GTE the rear brake discs had to be replaced at around 9000 miles due to rust and pitting (because the GTE does not have auto brake-cleaning, and i rarely ever used the pads).
But yeah, Kezo is of course correct. As soon as you slow down, basically, the lights come on.
To put the 1.3² into a more palatable frame: if you drive 30mph (around 13.4m/s) and slow down at 1.3², you come to a stop after 10.3 seconds (or around 70m). That’s equivalent to very light to light brake pedal pressure in an ICE car (engine braking into lower gear is around 0.5²).
Prior: SEAT Ateca Xcellence Lux 1.5 TSI DSG MY19, VW Golf GTE PHEV DSG MY23
Current: Hyundai Ioniq 6 Ultimate
Next: we'll see what's available in 2028.Recuperation braking do you mean regeneration braking.. YOU SHOULD NOT BE USING THIS AS A MEANS OF EMERGENCY OR NORMAL BRAKING THIS IS TO RECHARGE YOUR BATTERY AS YOU SLOW DOWN THAT’S WHY THE BRAKE LIGHTS COME ON BECAUSE IT DOES SLOW DOWN QUICKER.. THIS IS DANGEROUS DRIVING AND MUST STOP.. IF YOU ARE UNSURE ASK GOOGLE…..
@johno21 It is considered bad from to usse all capitals in form posts. It is deemed as shouting! So In future, if you post anything in capitals, it will be deleted. Fair warning given.
Joss
Current car: BMW X2 sDrive 20i M Sport 5dr Step Auto In metallic Portimão Blue. 04:10:2025
Previous car:Peugeot 308 GT Premium 1.2 Pure tech Petrol.@joejo is everything ok, given your question?
Yeah all good, I was having a discussion with another EV driver, she was convinced the brake lights didn’t come on when you used regen, I believed they did.
So now I know why I occasionally find myself behind someone who seems to keep braking for no apparent reason. I’d assumed that they were an apprehensive or poor driver 🤣
Yikes! Easy with the shouting. I always use the brake pedal, for extra control. Although it has to be said that the emergency braking system in my car once responded fractionally quicker than I did, and the brake pedal was already depressed when I got to it. Even when the car is slowing itself ‘cos I’m decelerating e.g. for a junction, my foot is hovering over the pedal to apply more pressure when it’s needed. The question was whether the lights come on, nobody mentioned relying on the system for normal braking.
Yes I was also confused by where that reply came from 🙂
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