What is the Blower Motor Switch all about?

In your car’s HVAC system, the heater core is what creates hot air to warm up the interior during cool weather. The air conditioner and its varied parts cools the air during the summer. The blower motor is what pushes the conditioned (heated or cooled) air out of the dash and into the cabin of the vehicle. Depending on the make and model of your vehicle, you may have one, two or even three blower motors, each with their own blower motor switch.

Essentially, the blower motor switch allows you to control the airflow within your vehicle. It lets you set the fan to off, low, medium or high (or a number of other speeds depending on the system in question). Over time and through normal wear and tear, the contacts inside the switch will wear out and it will fail, requiring a new blower motor switch.

Keep in mind:

• The blower motor switch isn’t inspected during any maintenance service.
• Most switches exhibit erratic behavior before failing completely, so you should have some indication about impending failure.

How it's done:

• The blower motor switch is verified that it needs to be replaced. The blower switch trim panel is removed for access.
• The defective blower motor switch is disconnected and removed from the trim panel.
• The new blower motor switch is installed into the panel and the panel is reinstalled.
• The blower motor switch is tested for operation on all blower speeds.
• The vehicle is tested to ensure proper A/C and heater operation.

Our recommendation:

Without a functional blower motor switch, you’ll be unable to control the fan and fan speed for your car’s HVAC system. That could mean anything from being uncomfortable, to being dangerously overheated or chilled depending on the weather conditions. If you suspect your blower motor switch is not working properly, have its operation checked by one of our expert mechanics.

What common symptoms indicate you may need to replace the Blower Motor Switch?

• Erratic operation (fan operates in some switch positions but not others, for instance)
• Blower motor will not operate at all

How important is this service?

Although a failed blower motor switch will not prevent you from driving, it is important to be comfortable in your car and have clear, unfogged windows. Have the problem inspected and repaired as soon as possible.