2005 pontiac vibe. Blower works intermittently. When it works, it works on all setting. When it doesnt, it doesnt work at all. Issue has been going on for a few weeks. Seems slightly better since it got cold outside. Went from working for 30% of the time to around 80%. We took out blower motor and it worked when connected to a battery. Theres a rubber vent or suction hose on the blower motor. Whats that for?
The next time the blower stops working, turn the blower speed to high, reach under the dash and rap on the blower motor with the handle of a screwdriver.
If the blower starts working, replace the blower motor.
I’m guessing that is to help cool the blower motor’s parts and/or to prevent pressure from building up inside the housing. If the problem continues, measuring the voltage at the blower motors power input will provide a clue. If the voltage measures ok but the motor doesn’t turn, either something the motor is connected to (the cage for example) is stuck, or the motor is kaput.