Blower Motor Not Working On Any Speed: 5 Root Causes & Fixes!

Blower motor not working on any speed may render you downbeat. It’s a frustrating moment and gets challenging to diagnose and handle.

Lucky you, right in this article, we will get you covered by leaking all steps to address such a dilemma besides its root causes. We kid you not!

Hit the road right now!

Blower Motor Not Working On Any Speed: Why?

Blower Motor Not Working On Any Speed

Why is my blower motor not working? Here are 5 common culprits: broken wire or faulty ground connection, a defective fuse, a bad motor, broken resistors or control modules, and problematic climate control units.

Poor Ground Connection Or Broken Wire

The poor ground connection can lead to the car blower not working on all settings and even AC turning on and off extraordinarily.

To test this, connect a short-term grounding jumper to the other motor terminal, and a fused jumper can be wired from a battery to the motor’s power side.

Finding and cleaning the motor’s grounding point will solve the problem.

Disconnect the electrical connections at the blower motor, then connect a multimeter to the motor to do more testing to see if the issue is a poor ground connection.

Also, the blower fan in the car not working is due to the wires in the circuit and the fuse box getting broken.

A Malfunctioning Fuse

A blown or bad motor fuse is the most frequent cause of a blower fan not working in car at any speed. A fuse is a tiny wire fitting inside a connector, protecting motors from electrical surges.

If so much current goes through the blower motor that it overloads, the fuse will blow and stop the motor from working. The fuse is typically in a panel or box under your car’s hood.

Once it’s defective, the only thing you can do is replace it.

The blower motor and the HVAC controller fuse should be checked since if either of these is blown, the blower motor will quit functioning.

Bad relays are connected to blown fuses as well. In essence, relays are just more oversized fuses.

In most cases, the blower not working in car at any speed can be because of a relay for both high and low speeds.

Bad Motor And Speed Control Module

The speed control module manages the motor speed. If the speed control module fails, you will face the car blower fan not working.

Unplug the electrical connector at the blower motor to test the control module. Disconnect the ground and power connections on the jumper as well.

You can disable the speed limiter. After that, attach a temporary grounding jumper to the other motor terminal and wire a fused jumper from a battery to the motor’s power side.

Bad Resistor Or Control Module

The blower motor resistor’s job is to limit 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 AC fan speed.

The blower motor may stop functioning if the resistor control module develops a malfunction.

When operating, a struggling blower motor brought on by internal component deterioration can stress the resistor, causing it to overheat and burn out. 

In some cases, even when the blower motor resistor fails, the motor may still run, although at high speed or locked at a single fan speed.

Still, if your resistor overheated and burned out, you can find your blower motor not working.

Defective Climate Control Unit

The air conditioner’s climate control module is the cornerstone of the system.

It operates the blower motor and regulates the temperature within the building. A non-functioning blower motor likely stems from a faulty climate control unit.

In this case, it may be hard to DIY. It’s better to bring your car to the repair shop and have them help you.

What Are Popular Poor Blower Motor Symptoms And Their Meanings?

blower fan not working in car

Your AC Fan Is Not Running

Even after turning on the AC, no air gets out of your vents. There can be a defective motor or a stuck blower wheel.

A broken fuse, relay, or resistor are some potential causes. Your fan may not be spinning upon closer inspection. The engine sometimes runs, yet the fan can’t turn.

Other issues can be resolved except for a burned-out engine. You could alter a defective relay or a fuse with ease, for instance.

Blower Motor Emits Weak Airflow

Unsatisfactory airflow may be due to the slowing-down automobile AC fan. Usually, the wiring, the resistor, or the motor assembly is the issue.

It denotes a lack of power, resulting in decreased speed for the motor. You may also notice a fan blocked with debris.

Remove the part with debris buildup. More prolonged exposure might result in burnt-out components and a blower motor that won’t operate at any speed.

Blower Motor Can’t Operate At All Speeds

Its speed may be controlled using a control module or a group of resistors. With a resistor-based blower only operating at the most excellent speed, it may get defective by corrosion or overheating.

Blowers that won’t run at the necessary speed or that cycle off and on are signs of a malfunctioning blower motor control module.

Car AC Fan Making Noise

One of the most prevalent signs of a malfunctioning blower motor is noise. The blower makes a rattling, screaming, or squeaking sound.

At this point, your motor may get worn out, mainly where the bearing or other moving elements are concerned.

Debris-like leaves stuck in the fan or assembly could cause a noisy blower motor.

Replace the whole assembly if the motor is worn. Depending on your blower type, change the engine as a separate component.

While you find the AC unclean, wipe out all debris.

Smoke Getting Out Of Car’s Air Vents

Be watchful to the car’s air conditioner spout smoke or white smoke when the AC is on. This results from melted insulation brought on by overheating wires.

Additionally, the burning scent is probably detected. One of the causes is current overload, a blocked fan, or a short circuit, making the motor work too hard to rotate.

Quickly stop the vents on your car’s AC from burning. If it occurs while driving, stop immediately, and turn off your AC and vehicle.

Before you use the automobile again, have a mechanic inspect it. The wiring, the resistor system, and other electronic components require a sparing check.

Blower Motor Not Working On Any Speed: How To Tackle

The decision to repair or replace anything is heavily influenced by age and many other factors. Many drivers need to clarify whether it is more cost-effective to have their item repaired or replaced.

In most cases, replacing an old heating system is more economical than repairing an older one.

But you can expect lower annual heating expenditures with a newer model because of its improved energy efficiency.

A professional HVAC expert can evaluate your furnace and help you weigh the benefits of replacing the blower motor against the cost and other considerations in your property and lifestyle.

Your furnace’s blower motor might be the source of the problem when it is producing unusual noises or failing for no apparent reason.

You may rely on professionals to fix any issues with your heating system.

Whether you need a new blower motor for your existing furnace or a whole new system, you can count on them for superior service every time.

How To Test A Blower Motor’s Components

How To Test A Blower Motor’s Components

Relay Test

A relay is part of several blower motor circuits. The relay activates the motor, completing the circuit that supplies power to the blower from the battery.

Learn the signs indicating a faulty blower motor relay.

Afterward, locate the relay and turn the AC on and off. A clicking sound ought to pop up.

Use a multimeter to check the power of other relays. If any is inoperable, throw it away and get a new one.

Fuse Test

Typically, a blower motor’s fuse will be hooked to the resistor pack. An extra fuse is often located on the dashboard.

Mounting a digital multimeter to the fuse is an easy way to check for breakage. If one end of the cable is blown, just that end will lose electricity. Supplant it.

Control Module Test

The speed of a blower motor may be regulated with either a resistor pack or a control module. The module’s electronics will control velocity thanks to the sensor signals.

Overheating and corrosion may ruin resistors, leading to a faulty blower motor.

Employ a scan tool to test the module’s health. Replace the module or resistor pack if needed.

Wiring Test

Toward bad connectors and wires, verify their functionality by doing a power check with a multimeter.

As an alternative, just looking can help check the connections between each component. Alter all corroded connectors, frayed cables, or loose wire harnesses.

Resistor Test

Resistors often reside in a resistor pack next to the blower, occasionally within the ductwork. Most resistor failures stem from corrosion or overheating.

A broken resistor is noticeable by merely looking at it, but a multimeter often reckons things more correctly. Test the resistor in a fan motor to see any damage signs.

Check the resistance individually by connecting the multimeter’s probes to the resistor. The resistor gets broken when the multimeter reads an open circuit or infinite resistance.

Go for the resistor replacement. Ensure the resistance values comply with what’s specified in the guide.

Final Words!

Now, the blower motor not working on any speed no longer makes you fret. After pinpointing the issues’ roots, the fixing step is much quicker and more precise.

From the bottom of our hearts, we wish you to have safe driving. But, if all efforts are in vain with the steps we shared above, it’s time to bring the car to the repair shop.

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