What does a blower motor transistor do?
The blower motor resistor is an electrical component that is a part of the vehicle’s heating and air conditioning system. It is responsible for controlling the blower motor’s fan speed.
Where does the power transistor go in a blower motor?
The power transistor has 4 wires: two come from the climate control system control unit, one is the ground, one goes to the negative terminal of the blower motor. The service manual advises measuring the voltage at the blower motor, then if not OK, at the power transistor and so on.
What does it mean when a blower motor resistor fails?
In our case the ohmmeter shows open circuit, which means the resistor has failed. Sometimes, a blower motor resistor might fail due to problems with the blower motor itself. This means after replacing the blower motor resistor, check if the blower motor runs freely and doesn’t make any noise.
How is the speed of the blower motor controlled?
The electronic module that controls the speed of the blower motor is called a blower motor control module. In some cars, the blower motor has only 4 or 5 fixed speeds. In this case, the speed of the blower motor is controlled by a blower motor resistor.
How much does it cost to replace a blower motor resistor?
The blower motor resistor or control module replacement is not very expensive. For example, one of our colleagues had a problem with his 2011 Ford Escape: the fan only worked at the speed 4. He paid $50 to diagnose and $112 to replace the resistor at a local Ford dealership.
Why do I need a power transistor for the blower motor?
This is due to the fact that the power transistor depends on the blower motor to function and starting your diagnostic with the power transistor, instead of the blower motor, could have you replacing parts your Honda doesn’t need. The following tutorial will help you test the blower motor in an easy step-by-step manner:
What causes a blower motor resistor to overheat?
Sometimes, the mechanical resistance to the motor rotation causes an excessive electric current that can overheat and prematurely damage the blower motor resistor. For example, this happens when the fan blade is jammed by a foreign object or when the motor bearings are worn out and it doesn’t spin freely.
Is the blower motor the same as the air conditioner?
The blower motor may not be the same brand, but it is important. You should understand that the blower motor matches amp draw, horsepower, voltage, RPM, and the diameter of the motor for remounting in the existing bracket.
What happens if the blower motor goes out?
The blower motor is really the heart of the HVAC system. Without it, you don’t have airflow in the system. If your blower motor goes out, you won’t have heat or AC. So if you turn on your HVAC and you don’t hear anything, you might start by checking out the blower motor operation.