Recently replaced the control module of the blower motor. Occasionally our trailblazer will have some symptons. The fan blower will not come on and visually appears all should be working fine. If i turn off the hvac off with the power button at the control head and turn back on, sometimes the fan will turn back on at what ever speed it is currently set at. Sometimes I have to pull the fuse(under rear seat) and the auto hvac system resets and the fan will work. curious if the control head is going bad? At over 200 bucks, I hope not. Just thinking the odds of a bad motor on the blower are slim given the symptoms. BTW, glad to see you on this site roadie