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Q: heating/cooling sysytem

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Back a couple months ago my motor blew so I got a new motor and resistor for my car thinking that would fix the heating/cooling problem but it didnt so what could be the problem ?

A: In the future, it helps if you include your...

In the future, it helps if you include your car’s year, make, and model. On all cars there are a few few other components involved in the blower motor circuit on your car.

Blower motor switch: This can be in the form of a automated module that controls the temperature, mode and blower speed. This type of system would be found on luxury cars. It can also be a simple four position switch. There are a few other configurations that are a combination of the two, but in every case, there is a switch, either automated or manually controlled that will send power to the resistor that controls fan speed.

Whenever we are testing an electrical circuit, the first thing that should be done is check all the fuses. Not just the fuses in the circuit, gut all the fuses. It is often difficult to know if another fuse powers a part of the circuit you are working on, even when it isn’t labeled as such. The simplest thing to do is to test all the fuses. If you find a blown fuse, you will need a factory wiring diagram to determine what it supplies power to.

Connectors commonly get hot and melt in this system. If you find a connector at the resistor, blower motor or blower motor switch, (keep in mind the switch could be a module, I don’t know because I don’t know what kind of car you have) that has been hot or melted, this will create a high resistance in the circuit and electricity won’t flow. Even if the connection looks good to the human eye, electricity doesn’t flow based on what we thing we see. The flow of electricity occurs at the atomic level.

If you decide to get this fixed I suggest getting your car looked at by a certified technician, such as one from YourMechanic, who can diagnose your A/C issue and make the necessary repairs.

I hope this is helpful to you.

Good luck!

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