Hello:
I have a Goodman GMP100-5 furnace. I have a random problem that seems to happen more often when it is cold outside.

The draft inducer blower will start up for only 1-2 seconds then will switch off causing the system to not turn on. If I manually reset the system off and on, the motor will sometimes successfully start up and then it will run fine as long as it isn't turned off (i.e. via the thermostat). Can someone please help me figure out the next steps to troubleshoot my issue.

Hook an electric meter to the motor wires. When the unit tries to start there should be voltage present. If the voltage is present and the motor will not start then the motor is hanging up or defective and needs to be replaced as an assembly along with the blower housing.

If the power is not going to the motor then you have a different problem and you will need to address the circuit board that supplies the voltage to that motor.

Thank you for your reply. I cannot get it to fail to start right now, but the voltage coming out of the circuit board is 123V which seems to be fine. I will try to measure voltage when it is acting up next time. But it seems like it could be the motor from what you said.

Does the circuit board shut off the voltage and "pause" the system if it doesn't think the motor is running? i.e. how does the circuit board know that the motor isn't running and shut the system off? When a repairman says your motor is pulling too many amps? What does that mean and how do I test it myself? Any other ways to test the motor?

When a repairman says your motor is pulling too many amps? What does that mean and how do I test it myself?

Buy an Amprobe and test the motor current draw then compare to the motor rate. If to high the motor is drawing overcurrent and that could ne a motor or a overspeed condition my improper motor wiring.

The system board no's nothing except for what the sensors and other controls tell it. Then the circuit board makes a decission as to what to do depending upon the imput from the other items..