It is located on the passenger side behind the glove box. If you remove the kick plate at the bottom of the underside of the glove box and look up you will see the module with the wire going to it. They are conected to the blower motor and you can trace them back. I you drop the glove box out of the way by slide the keeper to the side you can get to the wires to inplug them from the blower motor.
This and more info is available with pictures of how to do this change (easy) is available at our enthusiasts website:
www.trailvoy.com
i had a 03 Chevrolet Colorado, and the resitor was located under the glove compartment, where the motor blower is, the resistor is screwed to the side of the blower. hope this works for you. the resistor is usually located there.
location blower motor resistor 92 J30
If your 03 Trailblazer blows heat out of the back vents when set on AC sometimes, it could be because of a faulty blower motor resistor block.
If your 03 Trailblazer produces heat at the back, the problem could be attributed to a faulty blower motor resistor block.
In the switch assembly itself.
i have an 03 grand prix and yes it was the blower motor resistor also check there is a fuse for fan low and fan high or something like that
switch, relay or blower motor problem as a guess.
On 03 silverados i belive the blower motor relay is internal to the blower motor resistor. i could be wrong though, check the underhood fuse/relay panel for one.
There is not one in 03 TB but there is an access door down by the blower motor in the 02 and 03 TB, Envoys where you can install a filter. use the filter for a 2000 Silverado.
If you have a 2003 Trailblazer which takes 5 minutes before it starts, there could be a problem with the remote start or the ignition switch.
Blower motor resistor is bad.. Fan control is gated by stepping power down via resistance. When there is no resistance, you get one speed, high..
resistor needs to be replaced it is under the glove box by the cabin filter remove the black round box you will see it