flashing coolant light

[supersifi]

Hi,

could anybody tell me why my my coolant warning like keeps flashing? I have a 1994 Vento turbo diesel. The coolant level is at the max mark & the fuse to the radiator fan is functional and the fan works. The temp gauge reads between 80-90 degress whilst driving yet the light still flashes continually! any suggestions? .. thankyou.

[kite]

try cleaning the coolant level sesor in the bottle.
give the prongs a scrape with a screwdriver.