P0117 engine coolant temp sensor fault

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Active Member
Aug 9, 2015
W204 c250 cgi facelift petrol 2011
Mercedes c250 CGI petrol blue efficiency

Engine management light and fan constantly running, engine temp not increasing

I've had it plugged into the diagnostics, engine management light has cleared but fan is still running really loudly

Permanent fault code P0117 - coolant temp sensor 1 short to ground, engine coolant temp sensor 1 circuit low

It appears I have a faulty temp sensor, could anyone please provide the part number and instructions on how to replace the sensor
Look at the thermostat, it's most likely part of that 👍
It's pic 80 in the diagram which is separate to the thermostat, just need to figure out how to get to it!


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Managed to replace the cooling temp sensor without having to remove any other parts to get to it, all working now :)

Part no A0009056102 purchased from Mercedes £17.88

Hopefully this helps someone else out!

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