Nickgold03

Hello I’ve had the unfortunate go of repairs on my 2006 Mercedes c280. I recently bought this car and right after driving it home I’ve had my shifter module go out and throw me in limp mode. Around this same time I had a po128 code pop on and my radiator fan would run at full speed all the time. I replaced my shifter with a used one and fixed my shifting issue drives great now, I also replaced my thermostat, coolant level sensor, flushed new coolant, upper radiator hose, and my battery. Now with no check engine lights I still can not get my radiator fan to stop blowing at full speed on startup. Also after flushing my coolant I am met with a constant check coolant level and coolant visit workshop even tho my coolant is full and fine.

Any help or ideas is very much appreciated.

C230 Sport Coup

I'm not sure which sensor measures fluid level since fortunately, this particular malady has
not happed to me....yet. Well not exactly.
It was running with no key and engine off after being parked outside for
a long time in the rain, waiting for other repairs. I had to disconnect the battery. I mean after I charged it,
since it had gone dead in my absense presumeably from the fan running.
But later when it was dried out and was going to commence the other repairs,
it just fixed itself. But in your case, you have a good clue.
The ECU isn't seeing the fluid sensor, so either a loose connector or bad sensor.
I"m sure there's other fhreads on this if you search,

toolboxx

I also have a 2006 c280 recently purchased. I know it's been a minute since you posted this, but you never said if you had fixed the issue. I had the same problem, fan running at full speed as soon as the engine was started. Nearly killed my battery. In my situation I replaced the coolant temp sensor, the one on the back of the cylinder head that's not fun to replace. Problem solved. However I never had the low coolant level warning.