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The Reason Mercedes Benz Blower Motor Not Working

Published by: Jack
Date of Publish:

The blower motor in a car sends the heated air or cooled air out through the fan vents available on the dashboard. The motor sends the air out based on the car's selected fan speed and climate control settings. You can increase its speed or can slow it down. Mercedes Benz is a premium-class vehicle but can also have some issues.

If the Mercedes Benz blower motor stops working, you won’t get any cooled air or heated air out from the vents of your car. The air stops flowing through the ducts of the vehicle. There can be many different reasons why the Mercedes Benz blower motor fails or stops working.

Reasons for Blower Motor Not Working

• Faulty Fuse

One of the main reasons the Mercedes Benz blower motor is not working can be the faulty fuse. The blower motor of Mercedes Benz needs electricity to operate. So, if there is a defective fuse or blown a fuse, the complete circuit of the car gets broken, and the car's blower motor stops working. You can check the faulty fuse of a Mercedes Benz yourself by looking at the car’s manual or the fuse box cover. And if the fuse is blown, you can replace it with a new one. The sign of a faulty fuse is that the strip in the fuse will be broken from the middle. Always ensure the new fuse is of the same ampere as the old one. The direction of inserting the fuse in the box does not matter.

• Faulty Relay

A relay is a switch to turn the electrical loads on or off. Another reason for the Mercedes Benz blower motor failure can be the broken or faulty relay. You should check the relay if your car’s blower motor is not working. Different cars have relays located at other places in the car. Firstly, you should find the location of the blower motor relay in Mercedes Benz. You can learn about this in the car’s manual or the owner’s handbook. Mostly you will find the relay on the front right side of the engine or under the steering. When you have found the relay location in your Mercedes Benz, try to replace it with a new one or switch the relays. But always ensure that the battery is disconnected before replacing the faulty relay. Vehicles with an auto climate control feature do not have a relay for the blower motor.

• Faulty Blower Motor

If you turn on the air conditioner or heater in your Mercedes Benz and the heated or cooled air does not come out from your car’s air vents, this is because of a faulty blower motor. The blower motor of Mercedes Benz can stop working anytime. There can be some signs of a defective blower motor, like a loud whirring noise when you turn on the fan, weak air thrown through vents, a plastic burning smell, or grey smoke from the vents. All these can be the signs of a faulty blower motor in Mercedes Benz. If the Mercedes Benz blower motor is properly maintained, it lasts around 10 years, but sometimes, they stop working earlier for different reasons.

• Faulty Connection or Unattached Wires

A faulty connector can disrupt the electrical supply to the blower motor in an E-Class on the resistor module, the resistor module, or the temperature control unit. The blower motor may also stop functioning if a circuit wire becomes damaged, including a wire from the fuse box. Rats or mice can enter your Mercedes Benz compartment or even the dashboard and nibble on the wire coverings, which can lead to various electrical issues. If bite marks are found, thoroughly check the blower motor's cables, hoses, and electrical wiring for damage.

• Faulty Climate Control System

Most cars have climate control systems installed in them nowadays. Mercedes Benz also has a climate control system. The climate control system is known as the main brain of the air conditioning unit. You can control the turning on or turning off of the blower motor of your Mercedes Benz with the climate control system. If your car’s climate control system is faulty, then this could also be why the Mercedes Benz blower motor is not working.

• Faulty Resistor

The blower motor resistor's job is to regulate the blower motor's speed. The temperature control unit tells the resistor module to increase or reduce the flow of electric current to the blower motor when you change the speed of the AC fan in your Mercedes Benz. So faulty resistor can also be a reason for the Mercedes Benz blower motor failure. The blower motor may stop operating if the resistor module develops a malfunction.

As for relevant info, please check at What is a blower motor on a car, Why Ford F150 blower motor not working, and Why Dodge Ram blower motor not working

Does a Blower Motor Operate with a Bad Resistor?

Yes, a blower motor can operate with a bad resistor. But the working capacity of the blower motor will be fully reduced as the fan will only run at high speed and be stuck at only one speed. So it is highly recommended to replace the resistor of the blower motor if it gets bad or faulty. You can also replace the old blower motor of your Mercedes Benz if you want to have a tension-free drive.

How Can You Inspect a Blower Motor of Your Car?

You can inspect the blower motor in your car using the following three methods. Ensure you have the appropriate equipment. Because without the right tools and equipment, you can inspect your car’s blower motor.

  1. Check the blower motor for blown fuses using a voltmeter or an ohmmeter. Replace blown fuses as soon as possible.
  2. Check to see if the blower motor is operational by starting the engine. Now check for loose circuits if the fuse blows again.
  3. It's time to replace the car blower motor if the circuits are sound but the motor is regularly blowing fuses.

These are all the steps or methods you can follow to inspect your car’s blower motor.

Car Blower Motor Working System

To put it simply, the blower is geared to increase air intake by compressing it without creating a vacuum, which is how the car AC blower motor operates. A boost is created as additional air is forced into the engine. More fuel can be added to the charge to raise the engine's power thanks to the more air in the boost. Consequently, a damaged blower motor can quickly render a vehicle's HVAC system inoperable. This results in uncomfortable passengers and unsatisfactory driving experiences. Get the blower motor examined by a qualified technician as soon as possible.

What is the Lifespan of the Blower Motor of your Car?

The lifespan of your car’s blower motor mainly depends on the proper maintenance and handling of the vehicle. If you maintain your car regularly and protect it from extreme and heavy conditions, the car’s blower motor may work lifelong. But if you do not properly maintain your car and provide extreme and hard conditions, your car’s blower motor can stop working anytime. The average lifespan of the car's blower motor is around ten years.

Checking the Blower Motor Resistor

There are different methods to check the blower motor resistor. Frequently, a simple visual inspection discloses the issue. The rust can sometimes cause the car's blower motor resistor to fail. The resistance between both terminals must be checked with the specifications provided if the resistor has no visible damage. The resistor needs to be changed if the resistance is not within specifications. A blower motor resistor may occasionally malfunction as a result of issues with the blower motor itself. This indicates that after changing the blower motor resistor, ensure sure the blower motor runs quietly and freely. These are some of the methods or steps to check or inspect the blower motor resistor of your car.


Mercedes Benz is a premium car with some premium features. There are many different reasons which can cause the failure of the blower motor of Mercedes Benz. Some of the main reasons for blower motor failure can be a faulty resistor, faulty fuse, faulty relay, faulty wiring, unattached wires, faulty blower motor, faulty climate control system, or faulty connections. These all can be why the Mercedes Benz blower motor is not functioning. Always begin your investigation of this problem by checking for a blown a fuse or a defective relay in your car. If you are not experienced, you should get your car checked by a qualified and professional mechanic because it is simple to further damage your vehicle, particularly the electrical system. A qualified mechanic can quickly identify the problem for you. The repair cost of the Mercedes Benz is very high. You should always properly maintain your car and get it checked by a mechanic regularly because a poorly maintained car can create enormous problems for the driver. The blower motor for Mercedes Benz is a little bit expensive compared to other cars.

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