How does the relay work in a blower motor?
In a blower motor, the relay supplies the power that allows the fans to circulate warmed air. Essentially an on/off switch, the blower motor relay’s reactions start and end the heating process in HVAC systems by controlling the flow of current between the power source and the motor.
Where is the blower control switch on the dashboard?
The blower control switch on the dashboard controls the circuit flow of the blower motor to adjust the voltage from low, to medium, to medium-high, to high. When on high, the circuit bypasses the blower resistor.
What causes a fuse to blow on a blower motor?
If the blower motor relay develops any sort of problem that hinders its ability to properly limit and distribute power, it may cause the blower motor fuse to blow. Any sort of electrical spikes or excessive current from a bad relay will blow the fuse and cut power in order to protect the system.
What are the symptoms of a worn out blower motor?
One of the symptoms of a worn out blower motor is that it can intermittently produce a loud screeching noise when running. How to test a blower motor? If the blower motor doesn’t work at all, the blower motor itself must be tested first. Typically it’s done by measuring the voltage at the blower motor connector when it’s turned on.
Where is the blower motor resistor located on a car?
It’s located inside the dash, often on the opposite side of the steering wheel or inside the engine compartment on the firewall. A blower motor resistor or a blower motor control module is the part that controls the speed of the blower motor.
One of the symptoms of a worn out blower motor is that it can intermittently produce a loud screeching noise when running. How to test a blower motor? If the blower motor doesn’t work at all, the blower motor itself must be tested first. Typically it’s done by measuring the voltage at the blower motor connector when it’s turned on.
Where does the ground go in a Honda blower motor?
The blower motor control module (Honda calls it Power Transistor) supplies the ground. The power transistor has 4 wires: two come from the climate control system control unit, one is the ground, one goes to the negative terminal of the blower motor.
How does the blower motor work on a Honda Accord?
Typically it can be activated by pressing and holding different buttons. Testing Honda power transistor (blower motor control module). For example, in the 2009 Honda Accord, the service manual describes the procedure as follows: Turn the ignition to ON.
Why does my blower motor keep blowing fuses?
Relays are a vital protection against electrical surges. When the relay receives a jolt of strong current or simply cannot manage and distribute its load, it will send excess current into the fuse. This forces a shutdown which protects the entire system from electrical damage. Thus, blown fuses could be a sign of relay issues.
What should I do if my blower motor is not working?
The blower motor is crucial to the proper functioning of your HVAC system. This video will show you how to properly diagnose your blower by using the multimeter to perform an AMP draw as well as replacing the blower motor relay. Loading…
Where is blow motor relay located?
The blower motor relay is generally located in the under-hood fuse box or in the under-dash fuse box. A blown fuse can mimic relay failure. A failed blower motor switch can also give many of the same symptoms.
Where is the blower motor in a car located?
Some blower motors are easy to access, and others are buried under the dash. Most passenger cars and trucks have heater boxes and blower motors that are located inside the passenger compartment , but there are some instances where the heater box, blower motor, or both, are located in, and accessed from, the engine compartment.
Where is the AC blower relay located?
The blower motor relay is located in a wire harness connector that is secured to the Heater-A/C housing behind the glove box on the passenger side of the vehicle, next to the Heater-A/C wire harness connector in the passenger compartment.
Where is blower speed control module located?
The blower motor electronic automatic temperature control module is located behind the center of the dash panel . The blower motor speed controller is in the right rear of the engine compartment on evaporator and in some cars acts as the resistor.
When to replace a heater blower motor switch or relay?
When the motor gets old and tired it will draw more current through the wires than a new motor. It may still draw enough current to blow the fuse after it runs for a while. In that case, a motor replacement is in order. Step 1: Disconnect the battery. Put on your safety glasses and disconnect the battery at the negative cable.
What to do if your heater fan relay is not working?
Put everything back together the way it came and re-program the code into the radio if needed. If you’ve checked the fuse panel, and the fan motor doesn’t run at all, or if it runs only on the lower speeds, the blower motor relay may be at fault. Relays are used to carry electrical loads that are too large for conventional switches.
What are the symptoms of a bad blower motor relay?
One of the first symptoms of a bad or failing AC blower motor relay is a blown AC blower motor relay circuit fuse. If the blower motor relay develops any sort of problem that hinders its ability to properly limit and distribute power, it may cause the blower motor fuse to blow.
Should you run your blower fan without the air conditioner?
Running the fan without the AC can also increase the humidity in your home, since the AC won’t be drying out the fresh air being drawn inside. As for whether it’s helpful or harmful to your HVAC system to run the fan continuously, there’s no clear answer. Fewer stops and starts should reduce wear and tear on the system.
What controls the AC fan relay?
The condenser fan relay is the electronic relay that controls the power to the AC condenser cooling fan. When the relay is activated the AC condenser fan is switched on so that it can keep the AC condenser cool. The AC condenser is designed to cool down and condense incoming refrigerant vapor into cooled liquid and uses the fan to help keep it cool. The fan’s power is controlled by the condenser fan relay.