• Car isn't low on coolant
• Car doesn't lose any coolant, even over time
• Radiator was flushed / filled last winter and only started showing the light a couple of months ago
• Car never gets hot or overheated at all
• The light is on most of the time, but it is not always on

It is a 1991 190E 2.6.

Any ideas?

__________________
1994 C280, dark green metallic
105k miles

1991 190E 2.6, Black
191,500 miles
(sold to another forum member)

2003 Chevy Tahoe LT, Redfire Metallic
105k miles

1989 Mustang GT Cobra Convertible
43k miles