How to Test a Blower Motor Resistor?

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If you are having a hard time getting your air conditioning or heating system to work properly, it may be a blower motor resistor that needs replacing. When it comes to figuring out how to test a blower motor resistor, it is important to know what to look for. The resistor is a critical component to the functioning of your blower. It controls the speed of the fan and also provides a path to ground. A faulty one can affect your passenger compartment air and cause major issues with your air conditioning or heating system.

While there are many possible causes for your blower motor not performing to its full potential, a faulty resistor is a common culprit. You can easily identify a faulty one by performing the right tests, and then addressing the underlying cause. Once you have identified the problem, you can repair it or replace the entire unit.

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For starters, a multimeter will help you perform the necessary tests. The best way to do this is to take a close look at the resistance between the two terminals on the multimeter. Be sure to select the proper wattage for your car’s model and volts. This is essential to the testing process, as improper measurements can lead to bigger problems down the line.

If you are unsure about how to test a blower motor resistor, you might want to consult a professional mechanic. They can provide you with a blower motor resistor manual, which will help you to correctly identify the symptoms of the problem.

Another way to test the blower motor is by using a 12 Volt test light. By utilizing this method, you can avoid any electrical climate control system muddles. In addition, the 12 Volt test light will be the cheapest and most effective solution to identifying the problem.

One of the most important ways to test a blower motor is to test its fusible link. Fusible links are small pieces of copper that connect different parts of a circuit. These components can become damaged by high-current draw. Your mechanic can use an inductive amp clamp to find out how much current your fan draws and which connections are causing the problem.

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Other than the above-mentioned fusible link, you should also consider checking the main ground connection of the blower motor. If it is loose, it can be the cause of your fan acting in spurts and other oddities. Checking the ground connection will also prevent you from accidentally bypassing the fausible link, which can lead to a nasty explosion in your car.

Finally, be sure to check out the blower motor’s display to see what it is showing you. Its display should indicate the proper settings for your fan and air pressure. As you inspect the blower motor, look for the signs of wear and tear. Also, be sure to read the vehicle owner’s manual for more information on testing a blower motor.

Testing a blower motor is not a trivial task, and there are numerous other tests you should run to ensure your vehicle’s HVAC is working efficiently. Following these tests will allow you to quickly identify the source of your cooling and heating problems, as well as fix them.

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