Back to all

Such a Little Part (Climate Control Resistor)

October 18, 2020

You expect your heater/air conditioner to work like it should.  You have a control for temperature and one for fan speed.  You even have a control for what vents the air comes out of. 

Don't be surprised one day if your blower fan develops a mind of its own and starts going crazy.  Most of the time, you may find that it starts blowing at full speed, and nothing you do to try to control it does any good.  This is what may be happening.

Your blower motor has an electronic component called a resistor.  It does what its name says; it offers resistance.  When you want the fan to run more slowly, you turn the fan speed down.  That resistor accomplishes that by turning its resistance up.  When the resistor fails, the power has nothing to slow it and the fan speeds up. 

It's a small part and can fail due to age or corrosion.  It's usually not an expensive part, either, but it's often found in a location that's not that easy for the technician to get to.  That means labor costs will vary depending on the design of your vehicle. 

Occasionally, a faulty resistor can cause the blower motor not to work at all or only partially come on.  But other things can cause that as well, such as a faulty fan switch or vent control. 

This is where a technician's training comes in.  Special equipment can track down precisely where the issue is so you can be assured the correct part is being replaced.

It's just not pleasant when the blower motor isn't following orders.  Have your service facility check it out so you can be the blower's boss, like it should be. 

Perfect Tune Auto Repair
5434 S. Old US Highway 23
Brighton, Michigan 48116
810.227.9903
https://www.perfecttuneautorepair.com

Need Service?

Request a Quote

More articles from Perfect Tune Auto Repair

What's in a Number? (What Tire Numbers Mean)

June 9, 2025

You've probably never paid much attention to the writing on the sides of your tires, but they contain a wealth of information. There's a long combination of letters and numbers that can tell you a whole lot about what tires your vehicle was designed to be riding on. Let's check out this example... More

Smooth Operator (Shocks and Struts)

June 2, 2025

Few of us ever drive somewhere without encountering some pretty rough roads, and it's amazing how well our vehicles are able to smooth out the ride. Thank your shocks and struts. The two parts are similar. Some cars have shocks in the rear, and struts in the front. Others have struts all around... More

How Tired Are Your Tires? (Tire replacement)

May 26, 2025

Of the things you think about most, your tires are probably pretty far down the list. Thats understandable because todays tires are engineered to do their job without needing you to pay too much attention to them. But they DO wear out, and worn tires can contribute to skidding in bad weather, not... More