Blower motor only start working after i hit a bump.
- Bad blower motor brushes
- Blower motor faulty pigtail
In most cases that is a sign of worn down blower motor brushes not making a good contact. In some cases the blower motor/resistor pigtail could cause erratic operation of the blower motor too.
What is a blower motor?
The blower motor is a simple squirrel cage type of fan, DC electrical motor. It is located underneath the dash, usually inside the hvac case. Depending on the vehicle, there could be more than one blower motor
What is the function of the blower motor?
Ram air flowing through the evaporator does not provide enough air flow inside the vehicle for cooling purposes so the blower motor forces air past the evaporator and the heater core and out of the vents.
What are the main causes of a blower motor failure?
Noise from the blower motor due to a bad bearing or debris in the fan. A restriction in the cabin air filter that causes internal failure of the blower electrical parts and poor grounds are the main causes of failure and replacement of this air conditioning component.