Yes, Tesla brake lights come on during regenerative braking, but only when the deceleration is significant. This is to alert other drivers that the vehicle is slowing down, even if the brake pedal is not being pressed.
The Tesla manual states that the brake lights will turn on when regenerative braking is “aggressively slowing” the vehicle. This means that the brake lights will not come on if you are only lightly coasting to a stop. However, if you take your foot completely off the accelerator pedal at highway speeds, the brake lights will come on to warn other drivers that you are slowing down.
The brake lights will also come on if the regenerative braking system is limited. This can happen if the battery is cold or if it is already fully charged. In these cases, the brake lights will come on to alert other drivers that the vehicle is slowing down more slowly than usual.
It is important to note that the brake lights will not come on if you are using the Tesla’s “Creep” feature. Creep allows the vehicle to slowly move forward when you take your foot off the accelerator pedal. In this case, the vehicle is not actually braking, so the brake lights do not need to come on.
Overall, Tesla brake lights are a very important safety feature. They help to ensure that other drivers are aware of your intentions when you are slowing down, whether you are using regenerative braking or the physical brakes.