1999 Pontiac Grand Am 4 cyl Two Wheel Drive Automatic 131000 miles
My 99 grand ams blower has 5 speed blower control it would only work on 5 for about a minute so I replaced the blower motor resister I tested it after and all 5 speeds worked properly the next day all speeds still worked but would shut down after about 2 minutes I hope someone could help I am stumped.
When the problem occurs, I'd check the circuits at the blower relay. The orange wire is only hot for high-speed, voltage goes to coil side of relay. When relay is energized, that line with the arrow head on it, moves to the high-speed blower fuse. When the relay is not energized there is continuity for the lower speeds, blue wire carries voltage for lower speeds.
You could use jumper wires with inline fuse for voltage and ground to blower motor, blower motor should run as long as the wires are hooked up. If it still stops, I suspects a faulty blower motor.