Have Mercedes questions? Ask a mechanic for answers ASAP

Ask an Expert, Get an Answer ASAP!

Mercedes Blower Motor Questions

Is ineffective heating/cooling making driving uncomfortable? Is a nonfunctional defrost making driving your Mercedes dangerous? These are problems that could be caused by blower motor issues. The opinions of Experts will tell you if your Mercedes blower motor is faulty and what repairs are needed. Read below for more Mercedes blower motor questions which Experts have answered.

What could be the reason for no warm air flow in a 1998 Mercedes MB320 wagon when the vehicle is not moving and only minimal warm air when the vehicle is moving with the blower on maximum?

The fact that there is no air flow when the vehicle is at a standstill and only little flow when the vehicle is at speed means only forced air caused by the vehicle’s movement is blowing through the heater. This indicates that the blower motor is not working. The blower motor, which is under the passenger side dash, should be checked along with the blower motor regulator.

What could cause intermittent climate control operation in a 2001 Mercedes CLK430?

Case Details: All buttons light up and the controls appear to respond, but the system only works occasionally.

The symptoms described are those of intermittent blow motor operation. This happens when the brushes in the motor are bad resulting in only intermittent contact and operation. The other possibility, which is less likely, is that he blower motor relay is failing.  If the relay tests okay, the blower motor will need to be replaced.

What could be the reason for all the climate control panel lights to work and show that the fan speed is at high on a Mercedes S430 but no air to come from the vents?

If the climate control panel is functioning okay and showing an increasing fan speed but no air is being blown out the problem is probably with either the blower motor or the electronic blower motor regulator. The first thing to check is fuse #35 in the passenger side fuse and relay box under the hood. This powers the blower motor and if it is okay, the motor and regulator will need to be tested to see where the problem is.

What could be the reason for the blower motor with a new resistor on a 2001 Mercedes E320 to continue to run after the ignition is switched off?

The reason for this is likely to be the new resistor, especially if it is an aftermarket product. These are notorious for causing this and other problems with Mercedes blower motors. Fitting an OEM resistor should rectify the problem.

Why does the blower motor on a 1993 Mercedes 400E run only at low speed, irrespective of the actual speed setting?

Case Details: Hot and cold air is okay, but the speed is always low.

This problem is usually caused by either a faulty blower motor regulator or a failing blower motor. To see where the problem is the regulator should be bypassed to check if high speed operation now works. If it does, the regulator is faulty and needs to be replaced. If the speed remains stuck at low, the blower motor is defective and should be replaced.

If a faulty blower motor on a Mercedes S500 is being replaced should the regulator, that appears to be working okay, also be changed?

The normal practice is to replace both the blower motor and the regulator together as they tend to fail at about the same time.

What could be the reason for the blower on a 1999 Mercedes CLK320 to stop working when set to Defrost?

There are few possible reasons for this. The first thing to do is to check fuses 20, 25 and 26 which are all for the air conditioning and heating system. If the fuses are okay, the blower motor and the regulator which are mounted together under the passenger side dash will have to be removed. If a bench test of the blower motor shows no problems, the regulator is probably faulty and needs replacement. Worn blower motor brushes can cause the motor to work intermittently or not work at a high speed setting like Defrost.

How can the cause of the blower motor on a Mercedes CLK350 cutting on and off rapidly be determined?

The blower motor cutting off in this manner is usually caused by a faulty motor or relay. The connections between the relay and the blower motor need to be checked. The voltage at the blower motor needs to be monitored when it cuts out. If the voltage remains constant, the problem is with the motor. If the voltage cuts in and out, the problem is with the regulator.

What will a replacement blower motor and regulator, both OEM and aftermarket, cost for a 1998 Mercedes MB320?

The price of automobile parts varies according to where the purchasing is done and the type of store. That being said, the approximate cost of replacing the blower motor is $700 and the regulator is about $250. These are for OEM components. Aftermarket prices vary a lot but are usually significantly lower than OEM prices.

Determining if heating and air conditioning problems are caused by the blower motor or some other component of the climate control system requires detailed knowledge of Mercedes vehicles. The insights and guidance of Experts can help you find the best solutions to your Mercedes blower motor problems. Mercedes Experts are available online to answer all your blower motor questions.

Please type your question in the field below

3 verified Mercedes Mechanics are online now

Mercedes Mechanics on JustAnswer are verified through an extensive 8-step process including screening of licenses, certifications, education and/or employment. Learn more

MB Paul

Mercedes Technician

Vocational, Technical or Trade Scho

3567 positive reviews

Mercedes Technician

Associate Degree

30547 positive reviews
Michael Warfield

Factory Mercedes-Benz Technician

Vocational, Technical or Trade Scho

3132 positive reviews
See all Mercedes Mechanics