Low Coolant light stays on

I have a 2000 silvy. For the past couple of weeks, the LOW COOLANT warning light has remained on, despite the fact the coolant reservoir is full.

Could this be a bad sensor? Any ideas on troublshooting? Is it a pain to replace?

Any help welcome.

the switch is built in to the surge tank. remove the electrical connector and jump it. if the light goes out it's most likely the switch. replacing the tank is the only way, unless you leave the jumper in that will get the yellow light out of your face.

before you do that.. I would fill the tank first.. because I will get that light too even though the tank is full (or appears full) when I add more water to it it will go away.

I would fill the tank first.. because I will get that light too even though the tank is full (or appears full) when I add more water to it it will go away.
That's exactly what mine does...the light comes on, I add a little water and the light goes off...even though it was full to begin with.