High Blower Relay Replacement at your home or office.

Our certified mechanics come to you · Backed by our 12-month, 12,000-mile warranty · Get a fair and transparent estimate upfront

High Blower Relay Replacement Service

What is the High Blower Relay all about?

In vehicles that have manual heating, air conditioning and ventilation system, the blower motor serves to control the vehicle temperature through fan speed and air circulation. It does this by providing resistance to the blower motor circuit through a blower motor resistor when it is running at a low speed. The blower motor resistor works for all speeds except high speed, which is controlled by a relay on a separate circuit. The blower motor receives direct 12-volt power through the starter circuit when high speed is selected. If the high blower relay fails, the blower motor will not circulate air at all when high speed is selected while the remaining speeds still operate.

Keep in mind:

  • Blower relays often fail when the fan is working on high, but not on low.
  • A corroded blower resistor can cause the blower motor to fail.
  • No fan at any speed is a definite indicator of a bad high blower relay.

Our recommendation:

If you’re having problems with high fan speed on your car heating or air conditioning, then the problem could very well rest with the high blower relay. Our expert mechanics can check the voltage and determine if the relay is the problem, or perform other diagnostics to identify other issues that could be causing trouble with your car’s HVAC system. If it is deemed faulty, the high blower relay should be replaced.

What common symptoms indicate you may need to replace the High Blower Relay?

  • Car heater does not work
  • Air conditioning does not work
  • Fan speed operates on all speeds except full high

How important is this service?

This may not be a big problem in the summer, when you can always roll your windows down if you want to stay cool. But in the winter, you need high speeds for your car heater to keep you warm and defog your windows. It isn’t critical to have this fixed, but if winter is approaching, it might be a good idea to have it taken care of quickly.

Fast and easy High Blower Relay Replacement service at your home or office.

Recent articles & questions

How to Troubleshoot a Car That Makes Clunking Noises Over Bumps
Cars that make clunking noises as they drive over bumps may have worn struts or leaf spring shackles, or damaged control arms or shock absorbers.
How to Replace a Hydro-Boost Brake Booster
Diesel engines require a brake booster that is different from vehicles with engine vacuum. The hydro-boost unit uses power steering fluid pressure.
How to Replace a Power Steering Pressure Switch
Cars with a hydraulic power steering systems use a power steering pressure switch for hydraulic efficiency. A sign of failure is sluggish steering.

My car wont start but the check [engine](/topics-engine-chrysler/) and oil lights are coming on

Some time when im driving my truck i hit the smallest bump all my dash lights come on. As if my car cut off but it doesnt.

The instrument cluster electrical connections can become loose or have small amounts of corrosion in the connections to the cluster and other modules. This condition may require disconnecting the cluster and other modules and cleaning connections and adding some approved...

Can't find the Fuel Pump Relay on a 2003 Ford F-250 SD 5.4L

The fuel pump relay is behind the radio in an enclosure. To access the relay the radio must be removed. With a wiring diagram, you should be able to do some diagnostics to determine if, in fact, the relay is...

How can we help?

Our service team is available 7 days a week, Monday - Friday from 6 AM to 5 PM PST, Saturday - Sunday 7 AM - 4 PM PST.

1 (855) 347-2779 · hi@yourmechanic.com