Most car manufacturers use a series of resistors to make the heater blower motor run at different speeds. And when one or more of these resistors burn out, you’re usually left with only one heater blower motor speed—high. … Remove the screws, and swap out the resistor module.

How do you tell if it's the blower motor or resistor is bad?

Problems with a blower motor resistor are common in many cars. The most common symptom of a failed blower motor resistor is when the heater fan only runs at the highest speed setting (4 or 5) and doesn’t work at low speeds. In some cars, a failed blower motor resistor can cause a heater fan to stop working completely.

Why does my car blower fan not work?

If little air is coming through the vents (hot or cold), then it could be because the blower motor for the fan or a switch or resistor that controls fan speed isn’t working. Another cause might be that the electronically controlled “blend doors” that direct air flow are stuck or broken.

Why does my car AC only work on the highest setting?

The blower motor powers the fan that allows hot or cold air to flow from the vents in your vehicle. The blower motor resistor is prone to shorts, corrosion, and overheating. … When the resistor fails, typically, the highest setting is the only option that still functions.

What are the symptoms of a bad blower motor?

  • Poor or Airflow from Air Vents. This will be the first and most obvious sign your blower motor has a problem. …
  • No Airflow At All From Vents. …
  • Skyrocketing Energy Bills. …
  • Strange Noises When You Turn on the Heat. …
  • Overheating Blower / Weird Smells.

Why does my car AC not work on high?

If your air conditioner works on high, it is a very specific issue. It can mean that there is a problem with the blower motor, the control board, or the thermostat. However, we still do a full diagnostic check-up to ensure that all of the switches, wiring, and fuses could not be causing the same issue.

Why does my car AC not cool at high speeds?

The A/C thermal expansion valve (TXV) most likely is the cause of the A/C system freezing up at higher engine or vehicle speeds. … The A/C system should be performance tested and checked for pressures to make sure the system has enough refrigerant or the TXV is the cause of the problems.

Why is my car not blowing hot or cold air?

If your blower only works on the highest setting, your blower motor control module probably needs to be changed. If the fan isn’t working, you probably need to have the blower motor fixed or changed. If the air coming through isn’t hot, the heater core is probably clogged.

What is blower resistor?

The blower motor resistor is responsible for controlling the blower motor speed. … Each fan speed selection is connected to one or more of the resistors in the blower resistor assembly. The change in resistance controls the current through the blower motor, which in turn limits the speed that the blower motor spins at.

Why is my AC on but not blowing air?

The most common problems that cause a lack of airflow include frozen coils, broken fan and restricted airflow due to dirty air filters or vent obstruction. However, there are many other issues that can lead to minimal airflow, so it may be necessary to ask the professionals.

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Can you drive with a bad blower motor?

A bad heater blower motor will not affect the safety of your car, with the possible exception of you not being able to clear the windshield of snow, ice, or condensation if the defrosters don’t work. But you won’t be comfortable inside your car, especially during the cold of winter and the heat of summer.

Can you drive without a blower motor?

Your car’s blower motor is not only necessary for the operation of your air conditioner. Without a functioning blower motor your engine runs the risk of overheating. … Start car and see if blower motor works. If fuse blows again, check for loose circuits.

How much does it cost to fix blower in car?

In most instances this repair is on the relatively inexpensive side. A new blower motor will run between $50 and $100. Most blower motors sit in the dash underneath the glove box, and are accessible for replacement. Installation will run in the range of $80–$100.

Why is my car AC blowing warm air?

The most common cause of an AC system blowing warm air is a lack of refrigerant, though, you may also have a problem with your condenser. Other possibilities include a faulty compressor, broken cooling fans, or an issue in your electrical system.

How much is a blower resistor?

The average cost to replace the blower motor resistor at a repair shop is between $44 and $55 in parts and $70 in labor costs, for a total cost of around $114 to $125.

How do you know if your car AC compressor is bad?

  1. Odd Sounds. You might hear some strange noises when you flip on your vehicle’s air conditioner and if you do, it’s probably the compressor. …
  2. Hot Air. The whole point of turning on your vehicle’s AC is to get cold air to come through the vents. …
  3. Fluid Leaks. …
  4. Stuck Clutch.

Is there a fuse for the blower motor?

Many vehicles have two fuses for the blower motor, one in the interior fuse block and the other under the hood. The blower motor is usually under the dashboard on the passenger side.

What are the symptoms of a bad thermostat?

  • #1 – Temperature Gauge Reading Higher (or Lower) Than Normal.
  • #2 – Sudden Air Temperature Changes Inside Vehicle.
  • #3 – Coolant Leaking.
  • #4 – Rumbling Noises.
  • #5 – Heater Malfunction.

How do you know if your thermostat is bad in your car?

  1. The temperature gauge reads high and the engine overheats.
  2. The temperature changes erratically.
  3. The vehicle’s coolant leaks around the thermostat or under the vehicle.

Why is my central AC running but not blowing air in my car?

Your air intake is clogged, meaning that air isn’t getting in from the outside at all or isn’t circulating properly. There is a blown fuse in the ventilation system. Electrical issues such as a bad relay. Damaged blower motor.

How do you test a blower motor switch?

Test the switch. Plug the connector back in to the blower motor, and then trace the wire harness back to the connector closest to the blower motor switch, usually located under the dash. Disconnect the connector and set the multimeter to ohms.

Can you fix a blower motor?

There are a number of things that can go wrong with your heating system, but if the air stops blowing altogether and the same is true on cold air settings, a blower motor replacement is likely in order. The good news is that it’s a fairly straight forward repair.

How often do blower motors go out?

Even though the manufacturer states their blower motor will last two decades, we advise all clients to expect a 10-20-year life span due to age, use, and proactive maintenance.

How long does it take to replace blower motor in car?

This is around a 4 hour job by an experienced Tech. At home, by a Novice with decent skills, about 5 hours plus!