All You Need To Know About A Blower Motor Resistor In Cars

In this article we will discuss the blower motor resistor in cars, its primary function in cars,the symptoms of a malfunctioning blower resistor and where you can get replacement parts.

What Is The Definition Of A Blower Motor Resistor In Cars?

A blower motor resistor is a small electrical component that is part of the car’s heating and air conditioning system by controlling air flow. It is a passive two-terminal component that uses electrical resistance as a circuit element and contains controls to determine air settings..

What Is The Main Function Of A Blower Resistor?

Blower resistors in cars are resistors that are responsible for controlling the fan speed that supplies air to the passenger compartment of the car. It is designed to generate voltage in direct proportion to electrical current and thus allow the blower resistor to lower speeds. 

How Does The Blower Resistor Work?

Should the airflow exceed a predetermined amount, the resistor reduces air flow through the air vents via wire coils. Each coil has one speed setting - the thinner coils correspond to higher air settings and offer the least resistance which allows the fan to rotate faster, while thicker coils correspond to lower air settings and cause the fan to rotate slower.

Adjusting The Speed Of The Fan

The speed of the electrically operated fan can be adjusted either electronically by using the air conditioning system or mechanically by using a rotating lever. The blower resistor is usually located beneath the dashboard on the passenger side.

When using the heating/air-conditioning system on the dash, each setting represents a different flow of current, offering either less or more resistance. So when you select a low setting, less power is sent to the blower motor as there is more resistance and a high setting sends more power by having less resistance. In essence, the more power, the higher the speed of the fan and the stronger the airflow.

When The Blower Motor Resistor/control Module Malfunctions And The Signs To Look For:

The blower motor resistor can fail due to overheating or corrosion and is a fairly common problem in most cars. The overheating could be caused by a foreign object if it get in and jams the fan blade or when the motor bearings are worn out and interferes with the free spinning of the blades. 

These are the symptoms that would indicate that either the blower motor resistor is beginning to fail or has a broken control module.

• The air only flows at its highest speed setting (4 or 5) and the low speed settings do not work- this is the most common symptom

• Some of the air flow setting do not work 

• No airflow at all

Blower motor control module problems are less frequent, but it usually fails for the same reasons - corrosion or overheating. When the blower control module fails, you will find the blower motor doesn't work at all.

Blower Motor Resistor Replacement Parts And Repair

If the blower motor resistor or the control module fails, you can easily find replacement parts but it is wise to determine the cause of the problems before replacing parts. Some of the parts are not difficult to replace and you could do it yourself, depending on your knowledge of an electrical circuit, whilst others may need an experienced mechanic.

Ordering Replacement Parts Online At AfricaBoyz Online

You can order any air conditioning parts, air flow parts, blower motor resistors or blower control modules online at https://africaboyzonline.com/blower-motor and we will deliver directly to you or your mechanic. Online car part shopping is the way to go these days and you can get some great online deals. Check out our website now and see our wide selection of products for all makes of cars. All Parts. All Cars. All New.