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Does blower motor resistor affect AC?
The blower motor resistor is an electrical component that is a part of the vehicle’s heating and air conditioning system. It is responsible for controlling the blower motor’s fan speed. A failed blower motor resistor can cause issues with the operation of the entire heating and air conditioning system.
Can you bypass blower motor resistor?
In the highest speed state, the blower resistor is bypassed completely and the fan is connected directly to the car’s battery, which allows maximum current through the motor. Power to the blower motor is fed through the blower motor resistor, so if it fails or has any issues power can be cut off to the motor.
Why does my AC only work on full blast?
When a blower resistor fails, the highest fan speed usually is the only one that still works because it essentially bypasses the resistor and receives the maximum amount of voltage. When the resistor is working, it reduces the amount of voltage going to the lower fan speeds, so the fan runs slower.
What causes a blower motor resistor to burn out?
In most cases, a blower motor resistor fails due to corrosion or overheating. Sometimes, the mechanical resistance to the motor rotation causes an excessive electric current that can overheat and prematurely damage the blower motor resistor.
Why does my AC only work when the car is moving?
When the car is moving, versus stopped, there is more air flow over the condenser (the heat exchanger in front of the radiator) and that airflow is essential to system operation. Other possibilities are that the compressor clutch is not cycling as intended or that the condenser might be blocked or dirty.
How can you tell if blower motor resistor is bad?
Symptoms of a bad heater blower motor resistor
- Fan does not work at all, so no air comes out of the vents.
- Fan only works on some speeds and not others.
- Fan only works on the highest speed.
- Fan runs all the time and can’t be controlled with the fan switch.
- You see smoke coming out of the vents.
What to do if your air conditioner fan is not working?
Start capacitor not working: If your compressor is still working, your fan’s motor or start capacitor may not be working. You can try to troubleshoot it by pushing the fan with a wooden stick. Don’t do it by hand, since if the fan does start, it could cut your fingers.
Why does my AC blower motor not work?
The blower motor relay supplies power to this motor when you turn the switch to “on” that can sometimes fail. When this happens, you may notice that you will not feel anything blowing out of the vents at all. This may also cause the blower motor to work intermittently.
What are the symptoms of a failed blower motor resistor?
Blower motor resistor problems. Problems with a blower motor resistor are common in many cars. The most common symptom of a failed blower motor resistor is when the heater fan only runs at high speed and doesn’t work at low speeds.
What causes my air conditioner to run all the time?
Other problems that may cause your AC to run constantly include: 1 A stuck fan relay 2 A short in the thermostat cable 3 A thermostat that’s gone bad More