CD07SL550

Hi Everyone,

I have on 07 SL550 that the temp gauge will run normal for a while then move fairly quickly up to 120C. The indicator light remains white when this happens. If I shut the car off for a just a few minutes, temp drops back to normal. I have replaced the thermostat, temp sending unit and electric fan(this was defective). Also, I notice the fan is kicking on after short rides even though temp gauge is reading normal. There are no overheating smells or symptoms. Of course antifreeze is topped off. Any ideas what else this could possibly be?