The FEB light goes on when you shut TC off... BUT FEB is still ON
. You have to disable it in the menu to really disable FEB. Try it. No clue why both dash lights go on with just the TC button being pushed.
I have spent a lot of time messing with this.
Re the ECU cutting power. Maybe the ECU doesn't cut the power the gas peddle just stops working as giving it gas seems to do nothing. Same with the torque brake vectoring... if I floor it with TC on, with sand it feels like the car just "quits" for a bit, not a smooth brake application on the wheel while still trying to accelerate. Unlike they claim. Maybe they just disable the peddle signal, not disabling via the ECU. The effect is the same to me.
The only way I can get the power to continue delivering power on iffy traction conditions is to disable TC.
Now to complicate things it appears, from my testing, the modes control the intensity of the brake torque vectoring.
In std mode its quite agressive and sport+ much less so.
can elaborate on the above.
I spent quite a lot of time on a hill with 1" of snow playing with different combinations of modes and TC on and off, in each mode.
Try it. You may find it interesting. TC off in Sport+ is a blast. You can easily loose control, you can really put power down to all the wheels and spin them.. granted this can lead to the car not staying the road. Camber slip.
I don't want my brakes being applied or my power being interrupted (ECU or peddel signal) when I don't want it doing that. I want to control the power delivery with my foot.
HOWEVER on bad, slippery, iffy off camber, ice n snow roads, I may choose to leave the nanny tec on so I stay on the road.
All this is difficult to write clearly.