Q: hvac blower not working and 30A fuse blown

asked by on June 18, 2016

blower not working in car, checked and 30A hvac blower fuse was blown replaced and blew again

My car has 100200 miles.
My car has an automatic transmission.

That 30A fuse powers what is historically known as a blower motor resistor. In the case of your car it is a small computer called the blower motor control processor. It is simply a blower fan speed control. I would remove it and see if it looks melted or appears to have been really hot. I would expect you to find something like this, as this is a very common failure on all vehicles.

It is mounted on the passenger side above their feet, near the blower motor. It has five wires coming out of it. If once you have located this and removed it you don’t see anything physically wrong with it, I would unplug the connector to it and plug in another fuse. If the fuse doesn’t blow, you can be assured the wire coming from the fuse box is good. If the fuse blows with the blower resistor disconnected, then you have a wire shorted to ground somewhere from the fuse box to the resistor. Now you will need to locate it. I recommend running a new wire altogether if this is the case. Finding a shorted wire in the harness that runs through your dash will take many hours.

If the fuse doesn’t blow, the likely culprit is the blower motor controller. If there isn’t a sign of melting or being hot, I would power the blower motor with a jumper wire to see what it does. Ideally, you need an inductive amp clamp to monitor how much current the blower motor is pulling. If it exceeds 30 amps for a sustained period of time, I would replace it. Keep in mind, when an electric motor first starts working, the current will spike. Most likely above 30 amps. This is normal. What you want to monitor is the sustained current when the motor is operating. Most electrical systems such as this should run a current %50 to %70 of the maximum. Which in this case is 30 amps.

If there is a problem with the motor, you will likely have other indicators like, the motor won’t run, or it will get really hot to the touch. If you have determined there is a problem with the blower motor, I would advise you to replace the blower motor controller as well. They don’t take kindly to higher than designed electrical currents and it is likely damaged. Lastly, if the blower motor controller has been hot or melted, test the blower motor to make sure it isn’t pulling excessive current.

If you feel like you need some assistance with this, feel free to contact a certified mechanic who can diagnose your electrical issue with your blower motor resistor. Once that is done, they can assist you with replace your blower motor resistor as necessary and ensure that it’s properly functioning.

Good luck.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

What others are asking

I blew a brake line last night, replaced line.bled brakes from master cylinder, brakes very squishy

Both improper bleeding and a failed master cylinder could be the fault. Running the master cylinder dry can lead it to fail quickly. The primary seal on the master cylinder piston will tear easily. Make another attempt to bleed the...

Transmission hot idle engine , plus there is trans fluid leaking i think its coming from tbe filler but also have coolant leak

The transmission requires the cooling system to be working correctly to keep it cool. If you have the cooling system pressure tested and locate the coolant leak and get it repaired. You may have a water pump leaking. Once the...

If I replace my engine does it have to be the same year?

If you are looking to do an engine swap you should use the same year motor. This way you will not have different sensors and harnesses. Also you may have different exhaust, intakes, and accessories. From one year to another...

Front blower motor barely blows - 2012 Chrysler Town and Country

Check to be sure the cabin air filter is not blocked with dirt and debris. This is often an electrical issue, but there is always a possibility that the blower wheel has filled with debris if the filter is missing...

Ignition starts car, but engine won't catch

Hello! I believe the problem will be within your ignition key lock cylinder. There is a passlock sensor in the ignition key lock cylinder. This sensor is known to become bad overtime. Replacing the ignition key lock cylinder will more...

Kia Sedona has grinding sound when brake and release; signs of brake pad deteriorated

Always replace the front both or rear both at the same time. If the problem is just the pads, then you may need rotors also. I would do a complete inspection of all the brakes, and replace all of...

Battery hooked up backwards

As you may know, when the battery is hooked up backwards, reversing the polarity, will typically cause the alternator to fail. The fusible link is also likely blown. I would suggest performing a visual check in the fuse/relay box with...

Car starts and then dies

Hello. If I am not mistaken, that vehicle does not use a carburetor for the fuel system, that does not really matter though. If your vehicle is only starting when you add some sort of fuel, and not on it's...

my 2007 impala lt has been getting the engine power reduced sign and will cut my car completely off, i recently just bought a scan

The code is for the oil pressure is low or the pressure sensor is open circuit. This will cause the failure low power mode. I suggest having the oil pressure checked and if okay then replace pressure sensor to fix...

Related articles

Symptoms of a Bad or Failing Blower Motor Relay
If the blower motor does not function, car fuses are blown, or relays are melting, you may have to replace the car blower motor relay.
2012 Chevrolet Silverado vs. 2012 Dodge Ram: Which One Should I Buy?
When you are looking for a way to get a load of mulch or gravel, or need to haul a large trailer or boat behind your vehicle, chances are you are looking for a truck. Trucks are not meant to...
A Buyer’s Guide to the 2012 Chevrolet Tahoe Hybrid
Chevrolet Chevrolet has always had a good name when it comes to the vehicles they make, and that is doubly true for their SUVs. The 2012 Chevrolet Tahoe Hybrid has all of the great features that you would want from...