Beleive it or not I have both systems on this car. I replaced the temperature valve and the problem persists. I bought a control unit (thank you for the location) and apparently I was sold the wrong one, with the new one on it continues to start itself. I bought it from a german car parts recycling center. They take wrecked mercedes and salvage the good parts and sell them for a more reasonable price. The only problem are all sales are final and it as I said seems not to work right.