02 alero blower resistor

Sorry to bring this up again, but I just replaced the resistor on the car. The blower works on all speeds now, however on the first 3 speeds the resistor gets VERY hot. On the last 2 speeds it's cool to the touch. Is this normal?
ps the 2 last speeds were the only ones working before replacement. Any thoughts would be great.:banghead:
ps 2 I have not mounted the resistor to the firewall yet, as it is plastic; grounding should not be an issue.

Possible. What brand blower motor resistor was installed. Aftermarket or a GM/AC Delco?

I would expect the resistor to get hot on the lower speeds as it is providing more resistance to the flow of amperage to the blower motor so it will run slower. Basic electricity courses teach that with an increase in resistance, comes a corresponding increase in heat. This is also likely the reason that the lower speeds fail first, although I have seen some posts that said their windshield was allowing water to leak onto the resistor. I would think in these cases, the entire resistor would fail, not just the lower speeds.

It is working the way it should. While it is correct grounding of the plastic does nothing, the fan should not be run with the resistor not properly mounted. It relies on the airflow of the blower fan to keep it from burning up. And the original GM part burns up even with that airflow. For that reason, I would recommend an aftermarket one. Larger is better since it offers more surface area to give up it's heat in the airstream.

Lee Richardson
Mech-Tech

gm part, is aftermarket better?

Thanks for the info, if it goes again I will try one from autozone.

GM revised the original model of this part to address the high failure rate. I've had a revised resistor in my car for almost three years now, with no problems, but that's not to say it won't eventually fail again. If you got yours recently from a GM dealer, you got the revised version. In theory, it should last you a while.