Brand new 2015 SL, received the T/M malfunction while driving home from the dealership.
Was in stop-go traffic, rolled under an overpass at almost 0mph, the headlight auto-sensor detected "darkness" and kicked in the LED low-beams. Simultaneous to that, the main yellow warning lights came on and the "T/M Vehicle System Malfunction Warning" came up onto the driver vehicle status screen.
My theory is that since the car had just been sitting on the dealership lot perhaps the 12v aux battery was not in good shape and thus the problem.
Also I'm not sure if this is related but I'm not able to get the cruise-control to "set" the speed. I can turn on/off the main cruise control switch, but the set/accel toggle has no effect.