My 2005 does the same thing, just found out it's the blower motor control module. Hope that helps out!!
location blower motor resistor 92 J30
on the passenger side firewall
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.
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.
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.
I have an 03 deville and found my blower motor under the dash on the passenger side. It was intermiitant so I took it out and cleaned it. Works fine but I am planning on getting a new one as the brushes are close to worn out. I would advise you do the same
It's possible that it is a faulty fuse switch.
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 your 03 Trailblazer produces heat at the back, the problem could be attributed to a faulty blower motor resistor block.
If the internal heater blower on your 2003 Renault Grand Espace isn't working, first check the fuse related to the blower motor, as a blown fuse can cause it to stop functioning. Additionally, inspect the blower motor itself for any signs of damage or obstruction. If the motor appears functional, the issue may lie with the resistor pack or the control switch. If you're unable to diagnose the problem, it may be best to consult a professional mechanic.