Thread: HVAC Blower Motor

Is it common to have the blower come on at what seems to be a slow setting in auto mode (temp @90), and not be able to change speeds in manual?
Usually in auto with temp at 90 the speeds goes up to max. However if in manual mode there is no change of speeds.
Based on what I have read, I am thinking it’s the resistor.
Maybe the BCM?
Maybe the motor itself?
Any help would be appreciated.

By the way, it comes and goes.