How can I tell if my blower motor resistor is bad?
Attach the clip lead of the test light to a good ground like a bolt screwed into metal, and touch the sharp probe end to the terminals on the fuse. An indication of power at both terminals of the fuse determines that the fuse is good. If one of the terminals has power and the other does not, the fuse is bad. Replace the fuse as needed.
Where is the fuse on a blower motor?
Locate the fuse for the blower motor in the owners/service manual. Test the fuse, with the ignition key on, using the 12-volt test light.
What does the blower motor resistor do in a car?
The blower motor resistor is an electrical component that is a part of the vehicle’s heating and air conditioning system. It is responsible for controlling the blower motor’s fan speed. When fan speed is changed via the knob on the instrument cluster, the blower motor resistor changes setting, which changes the speed of the blower motor.
How do you test the power of a blower motor?
Unplug the blower motor and test for power using the 12-volt test light in the same manner as explained in Step 1. Testing at the motor itself eliminates the possibility of confusion caused by complicated electronic blower controls found in Electronic Climate Control systems.
A repair manual can tell you where its location is in your vehicle’s make and model. Inspect the resistor visually. Look for obvious signs of corrosion and burns from overheating.
How much does a blower motor resistor cost?
Depending on the manufacturer and model, a blower motor resistor can go anywhere between $3 and $335 on CarParts.com. The replacement parts come in individual units, sets of two resistors, or as part of a blower motor resistor kit.
Why are there so many resistors on a blower switch?
The blower switch and its gang of resistors are wired so that when the blower switch is set at the lowest speed, the maximum amount of voltage is dropped and the least amount of current is fed to the motor because it is passing through an entire series of resistors – for our purposes we’ll say there are three resistors.
What to do if your blower resistor Burns?
Look for obvious signs of corrosion and burns from overheating. If you see signs of overheated connectors, replace the blower resistor and its connector, but again, you must splice the wires right, or you’ll have problems at the splice later on.
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.