7 replies to this topic

[MikeRotherham]

Have owners of cars with regenerative braking observed just when the brake lights illuminate?

 

I have a Peugeot 208 a self charging mild hybrid.

 

The moment you remove your foot from the gas pedal and the car starts to slow down the brake lights come on.

 

In a conventional car you would remove your foot from the gas to slow with engine braking the brake lights don't come on so why this car is so sensitive I really don't understand.

 

It causes a problem because drivers behind get annoyed at the brake lights coming on and attempt to overtake some times at odd places.

 

Are all EV's and hybrids like this?

[Ethel]

Great question - never crossed my mind about the ID3 in da fam

 

"Lifting off the accelerator increases regenerative braking (recuperation). If the resulting rate of slowing down crosses the car's programmed deceleration threshold (typically around 0.13–0.15g), the brake lights automatically turn on." - I'd think that's most of the time, it seems to do more than engine braking in a petrol car.

[humph]

Having experience of several EVs I'd say that most if not all use this same function, but none of the ones I've driven have been as sentisitve as you describe.  As per Ethel's post my experience is that if you ease off the gas the brake lights don't normally illuminate, but if you lift off  quickly or completely then the lights do trigger.  One point would be is that regen braking intensity varies from one car to another, with some EVs not having an official 'one pedal drive' capability. In most cars the intensity of the regen braking will vary depending on the speed you're travelling. For example, once you're used to it, you can drive my Tesla without having to touch the brakes at all except in an emergency, but the BYD cars have virtually no brake regen so these need driving like a petrol car. 

 

I believe that the criteira on whether brake lights come on is regulated. From Google

 

In modern electric cars, brake lights are no longer triggered solely by pressing the physical brake pedal. Instead, they are governed by international safety regulations (UNECE Regulation 13-H).

The rules dictate exactly when an electric car must warn the drivers behind you: 

• Deceleration above 1.3 m/s²: The brake lights must come on automatically.
• Deceleration between 0.7 and 1.3 m/s²: The manufacturer is allowed to choose whether the lights come on.
• Deceleration below 0.7 m/s²: The brake lights must remain off. 

Edited by humph, Today, 10:49 AM.

[MikeRotherham]

Some good answers there some food for thought

 

I generally let the regen braking do the slowing down so I rarely need to apply the foot brake.

 

Perhaps if I did use the foot brake more I wouldn't get frustrated drivers over taking.

Edited by MikeRotherham, Today, 03:29 PM.

[stuart bowes]

can you switch that on and off / can you adjust the level of braking when you let off the "throttle"

 

seems like that would take some getting used to after so many years driving cars with engines in them.. surely it's natural to let off and assume it will coast along a bit, i.e. you don't always want it to start slowing down straight away just because you're not accelerating 

 

I'll have to have a go in one one day I suppose just to see how weird it all feels lol

 

on a different tack, I suppose there's a similar risk from the other side of the fence; if you're having a sprited drive in a manual petrol engined car, there are times you block change 4th to 2nd, rev match, re-engage clutch and then let off the throttle, that will slow down quite quickly without brake lights, does one check behind them for tailgaters first?  they might get caught out 

Edited by stuart bowes, Today, 03:57 PM.

[Quinlan minor]

I suppose there's a similar risk from the other side of the fence; if you're having a sprited drive in a manual petrol engined car, there are times you block change 4th to 2nd, rev match, re-engage clutch and then let off the throttle, that will slow down quite quickly without brake lights, does one check behind them for tailgaters first?  they might get caught out 

That'd be their responsibility to maintain a safe distance, wouldn't it?

[Steve220]

Ive had 2x tesla model 3s and a model Y. All of them put the brake lights on when regen braking 👌🏽

[stuart bowes]

I suppose there's a similar risk from the other side of the fence; if you're having a sprited drive in a manual petrol engined car, there are times you block change 4th to 2nd, rev match, re-engage clutch and then let off the throttle, that will slow down quite quickly without brake lights, does one check behind them for tailgaters first?  they might get caught out

That'd be their responsibility to maintain a safe distance, wouldn't it?

Well sure, but does anyone want to be in the position of arguing over whose fault it is, or rather just not have a caved in rear end in the first place? It was more of a point of interest along similar lines about how brake lights operate or don't necessarily indicate what's really going on

If you're driving that way and someone still right up your behind probably fair to say they're driving really badly or you're in a a race of some kind (legal or otherwise)