2008 Mercedes Benz C300 Traction Control

Computer problem
2008 Mercedes Benz C300 6 cyl Two Wheel Drive Automatic

2008 with only 13,000 miles, rear wheel drive, ESP and Traction Control, factory all season tires.

In a recent snow storm, car went up two hills with ESP yellow triangular light blinking intermittently. However, on the next hill near our house, the engine rpm DROPPED TO IDLE, yellow ESP light blinking. Car had to be towed! When it was towed a few feet to the bed of the truck, the front wheels were LOCKED, with transmission in neutral and parking brake off.

I had it towed to my driveway. Driveway is LEVEL and had only 2 inches of snow. When I pressed gently on accelerator with ESP turned on, left wheel spun then ESP braked it. Right wheel would not turn, and ENGINE RPM went to idle! Turned ESP off, one wheel would spin continuously and at least the engine rpm would be high and not go to idle.

The next morning we called service. They tried it and it worked! Tow driver said these cars are full of sensors and maybe snow/ice affected a sensor. Still had it towed to Mercedes dealer who said traction control is supposed to drop engine rpm to idle so people do not blow up the engine. Believe me, when ESP was on, it would not try very hard at all before lowering engine rpm to idle. The OTHER WHEEL NEVER EVEN TURNED!

Cannot find any technical service bulletins on this issue. Mercedes dealer said to buy snow tires.

My question is the traction control braking too much? The other/opposite wheel never turned. And the engine rpm dropped to idle almost immediately, as if a sensor was way out of adjustment.