How are the resistors arranged in a blower motor?
Heating systems with just 3 or 4 speeds use a motor resistor along with the speed switch to regulate the motor speed. The resistors are arranged in series to reduce the voltage in steps, depending on where in the series you apply power. Blower resistors can burn out. When that happens, you lose that speed.
Why is the resistor not working on my blower?
Hi There, The resistor is what controls the speed of the blower motor, not the relay. The blower motor relay supplies power to this motor when you turn the switch to “on” that can sometimes fail. When this happens, you may notice that you will not feel anything blowing out of the vents at all.
How is the speed of a blower motor controlled?
This means that the current running through the blower motor, and thus is speed is controlled by the resistor value. The user chooses a suitable fan speed by using a selector to connect one of the resistors in the blower resistor pack. Blower resistors are made of several resistors with different resistances.
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.
How does a resistor work on a blower motor?
Other car makers reverse that and run power to the blower motor first and terminate ground at the blower fan speed switch. By it’s very nature, resistors resist the flow of electricity, much like a flow restrictor in a pipe.
What are the symptoms of a bad heater motor resistor?
Symptoms of a Bad or Failing Heater Blower Motor Resistor. 1 1. Blower motor stuck on one speed. A common symptom of a faulty blower motor resistor is a blower motor that is stuck on one setting. The blower 2 2. Blower motor does not work on certain settings. 3 3. No air from the vehicle’s vents.
What’s the problem with my blower motor fan speeds?
Probably a bad blower motor resistor you have there, or possibly a faulty blower motor or switch. The most common thing would be the resistor assembly, as that goes out more often than the other parts. A quick check with a test light can determine failure. No Heat In My 2000 Chevrolet Malibu – Blower Not…
Can a broken motor switch stop a blower?
A broken blower motor switch can also stop the blower from changing to certain speed settings. If your blower motor cannot change to certain speeds, check both the resistor and the switch on your dashboard. The most common failure points are the resistor and the motor itself.