I've been asked this question by a friend, but obviously I don't know. When I go downhill or approach a junction and release the accelerator, the regen 'meter' shows how much resistive braking is applied, but at this stage I don't know if the brake lights are on. When I need more regen, a slight pressure on the brake pedal increases it gradually and as I increase the pressure  I get maximum regen,  so the brake lights will be now on. Until I come to a halt, I don't know how much effort is applied by the disc brakes. Incidentally, regen braking effort is why the Enyaq has rear drum brakes. To quote from a review of the 'yaq: Braking is strong and progressive. Interestingly, the rear brakes are old-school drums, rather than discs, because they’re used so little due to the regenerative braking of the electric motor that discs and pads wouldn’t have been scrubbed enough to keep them in good working order. That’s Skoda’s reasoning, anyway. So Octy iV pad wear should be much reduced.

Ask your friend if he/she can drive behind your car ja look when breaks lights are on. You can phone each other and you tell when you regen or when you brake?

1 hour ago, Jim2015 said:

release the accelerator

If you didn't have regen, would the brake lights come on now? Even if you dropped a gear or 2 as you released the throttle?

19 hours ago, KenONeill said:

If you didn't have regen, would the brake lights come on now? Even if you dropped a gear or 2 as you released the throttle?

No, but the regen is a different matter. As it applies braking effect according to gradient (when the DSG also drops gears down) I'd have thought that it would be sensible for the brake lights to come on. The Kia Soul EV brake lights come on if the accelerator is lifted off, but as it has a 62 kW motor, the regen braking is quite sharp.