Heat/defrost not working!

I have a '92 gp; Last winter my heat and defrost worked fine but this year when it started to get cold a little red light came on that said low coolant but after about 10 minutes of driving the light went away. I drove to the full service gas station and told him to check it cuz i thought it was full and he also said the level was fine. What do you think is wrong?

It sounds like a dirty coolant level sensor. As long as the fluid level is proper, don't worry about the light.

Are you saying the low coolant light came on , and you're getting no heat? You could have a stuck thermostat that isn't allowing proper coolant circulation.

Yeah thats exactly it i mean even last winter my heat didnt start working until that low coolant light shut off now this year it goes away almost right away but never any hot air.

change the thermostat, make sure you buy a 195 degree, as they give you better heat in winter.