Heater/AC Blower fan would not come on this AM in my Impala

I have a 2003 Impala LS. I got into my car this morning and when I went to switch on the defrost/heat nothing happened. Now, I have had issues with settings 1 and 2 not working for at least the past year but 3/4/5 all worked fine till this morning. From what I could tell the rear window defroster seemed to work okay but not sure how well it worked as my back window did defrost. I am thinking could it be a blown fuse? I believe from looking the fuse box on my car for inside the car is on the side of drivers side dash, but Im not sure which fuse I should be looking for. Also, don’t know if this matters or could cause an issue, but last night on my way home from work I stopped on got my car washed and the place used a lot of soap and water. IS it even possible that some water got down into/on the blower motor and with the sub freezing overnight temps it froze up the blower motor similar to how your windows freeze overnight from water on them? any suggestions would be great.

Car: Impala
miles: 140000

That is a hint for sure. You most likely need a blower motor control module. About $30 to buy, not sure how hard it is to replace on this car.

Check the fuse, just to be sure. Your owners manual has a map of the fuses in your car. Look in there for the HVAC fuses. There is probably a fuse box under hood as well.

Yu could wait for a warm-up to test your frozen blower motor theory, but the blower is not hat vulnerable to water entry so it is unlikely to be a solution.

I’m not sure if I still have the owners manual I will have to take a look.

They are available online in PDF format. Just go to chevrolet.com and search.

Yep found it, will check after work, if that is not the problem and it is the module I may have to look into just trading in and getting a new car, called 3 different places and all want $500+ to replace the module and with how old car is other issues that soon will have to be addressed it might be time to look into a new car with fewer milage and not 15+ years old…

$500? It must be a bear to get to the module. Well, that $500 is not even a good down payment and barely one months car payment or lease payment.

As long as rust is not an issue and the car drives OK, $500 isn’t too much of a repair for a car with at least another 30K miles in it. And if you trade it, they will knock money off the trade for the broken fan.

Blower motor modules can be expensive if your car has automatic temperature control.

If your car has manual HVAC controls you may need a blower resistor block.

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Well according to Youtube that module is basically just under the dash on the passaenger side of the car, if I had any mechanical ability I could probably do it but the three places I called all said they would have to do a complete service check on all aspects of the system and then to remove the covering and then remove the part and reinstall could total up with labor to close to $500.

As for the car itself it’s soon going to need all new struts and shocks which won’t be cheap, two new front tires, all the belts replaced and at somepoint address the oil leak (loses about a quart every 1000 miles). The hoses will soon need to be replaced and my gas guage doesn’t work either, so there are things that are going to need to be addressed in the coming months/years. The car is 15_ years old, topping 140,000 miles so while it’s not a for sure, I am going to start looking at other options, only issue is monies still owed on this car and rolling it over onto a newer car.

Bertrand, I think that is who you were before becoming dn4192. If I read your other posts correctly you bought this vehicle used in Dec. 2014 and you still owe money on it ? With all the problems you have had I would have bailed long ago.
At least the places you called gave decent estimates as to how much it could cost.

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Yep still owe about 23 months of payment on it, due to a bankruptcy and needing to have low payments (my monthly payment on it is $160) meant a 5 year loan. So I still owe a bit on it. I have tried to bail on it a few times, but again when you have a set budget and a limit you can spend on a monthly payment which now for me is $225 has made it impossible to trade out of it. Since trade value isn’t more then about $1000 at best that means some monies needing to be rolled over on the new purchase. So we keep looking and may end up having to come up with the $500 and get it fixed if that part is the issue.

You might get lucky and it is just a blown fuse. Blower fuses are usually in the passenger compartment, often just to the left of the driver’s knee. If not there, look on the other side, to the right of the passenger’s right knee. The underside of the fuse box cover usually contains a drawing of what all the fuses are for. If it is blown, make sure to replace it with a fuse of the exact same current rating.

Blower speeds 1 and 2 were inoperative on my sons Pontiac when I bought the car, I doubt this is the reason the previous owner gave up on the car. A replacement resistor block was $15 and 10 minutes of effort.

You may need to replace the blower motor and resistor block. Set the blower on high and tap on the blower motor. If the blower starts to operate the motor brushes are worn/stuck. Replacing both may cost $300 or more.

I tried to get the fuse box cover last night but it was on there tight so will have to work on it this weekend. I noticed that when I go from setting 4 to 5 there is a clicking sound coming from under the dash on the passenger side of the car and it’s pretty clear to hear it but only sounds between 4-5 but not between any other setting. From watching YouTube that is where the module is located.

The clicking sound is likely the relay that supplies full power to the blower motor on the highest setting. The other settings are based on resistor dividers to reduce the power to the motor. See Nevada’s advice above…

What is automatic temperature control? My heating/cooling system has a switch with a 1-5 on it to determine how fast the fan blows I guess and they two guage like levers that you move up or down to decide how hot or cold the air coming out is to be, one lever is for the driver side the other lever is for the passenger side. There are two buttons to determine either outside air or recirculated air and that is about it.

The fan speed is varied by manually varying the voltage to the fan motor. The speed of DC motors is controlled by changing the applied voltage. This is accomplished by simply putting a resistor in the circuit, “dropping” some of the 12VDC, thus leaving less for the fan motor. More resistance means less applied voltage and a slower fan speed. Your system has a stepped resistor of four levels, the fifth level having no resistance at all in the circuit, allowing the full 12VDC to be applied to the motor.

Generally you’ll lose the speeds one by one as the resistive sections of the “stepped” system burn out. The resistors convert the voltage they “drop” directly into heat, so they’re generally mounted directly through the duct wall into the airstream in the duct, helping to cool them and extend their life. On a 15 year old car, they’ve probably lived a full lifespan.

I’ve replaced a few of these resistor networks, and how hard they are depends on the duct & dashboard design and on your own dexterity. I could not change one anymore. I can’t crumple myself down under the dash anymore.

On some cars, you just set the temperature you want and the system does the rest.

The person who started this thread has traded this vehicle off and has another thread about the replacement. As they say in the cartoons " That’s all folks ! "

Re: What is automatic temperature control?

I think that terms means the hvac system does whatever is necessary to keep the passenger compartment at the selected temperature. In “heat” mode, if the temperature is below the setting, it may increase the flow of coolant through the heater core and/or may increase the blower fan speed. It’s a thermostat controlled system in other words. It’s sort of like how your thermostat in your home keeps the temperature fixed to where you set it.

With non-automatic temperature control such as is used w/my Corolla, the fan speed and coolant flow through the heater core is fixed once the drivers sets the controls. There’s no thermostat involved. If the ambient temperature gets warmer, I have to manually lower the settings otherwise it would get too hot inside the passenger compartment. I have to say, it’s a job barely within my skill-set, but somehow I manage :wink:

Reminds me of this early Seinfeld dialogue …