The low coolant light came on and the heater blows cool air on and off. on 2002 Pontiac Grand Prix

The low coolant light comes on after a while it goes off but comes on back again. The heater blows cool air longer than usual it does get hot after a while.

Asked by for the 2002 Pontiac Grand Prix
First, check your coolant level and top off if necessary. It may be the thermostat is starting to malfunction and need replaced.
1 more answer
I would top up antifreeze and pressure test system for leaks