I removed the tank and sensor.
The floater inside is moving but after some detergent wash it was the same did not sense the coolant.
The tank is very dirty inside lots of sludge on side walls.
Should waiting over night do a repair with radiator cleaner inside(after removing the tank)

I already changed the tank but after sitting in grout cleaner overnight sensor started working in the old tank.
If your tank is too dirty keep in strong cleaner overnight. 2010 3.6tdv8 180k km.
sold 06 td6 160k
Sold 03 td6 260k

Getting there, run some flushing agent through the system, run it for a week, then drain, flush and refill... Pete

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2014 L405 Autobiography SDV8 4.4 Loire Blue Ebony interior
2011 L322 Vogue SE 4.4 TDV8 Baltic Blue. Parchment over Navy Interior. Sold
2012 L322 Autobiography 5.0 Supercharged Ipanema Sand, Jet Interior. Sold
2002 L322 Vogue 4.4 V8 Epson Green, Ivory over Aspen Interior (Fatty Offroader) Sold
-Click for Project Fatty off roader-