YES!!!! They do. See my post. E-Brakes were killing me from getting my RAM towed.Had to tow my truck a few days ago because of a dead battery and a fried 48v Battery pack(Etorque), Releasing the eBrake was such a pain!!!! but after 20 minutes of trying with a jump starter hooked up, we did manage to release the eBrakes and load the sucker on the flatbed...
They have to install a fail-safe on these systems. No power - No Ebrake!!!! smh...