How Do You Test A Blower Motor Resistor

March 09, 2024 Post a Comment

How do you test a blower motor resistor

Here are some common signs that your vehicle's blower motor resistor is bad:

<ol class="X5LH0c"><li class="TrT0Xe">Loss of HVAC fan control (total or certain speeds)</li><li class="TrT0Xe">The fan only works on its highest speed setting.</li><li class="TrT0Xe">No air coming from vents.</li><li class="TrT0Xe">Intermittent or inconsistent fan speed.</li></ol>

Can a blower motor resistor be bypassed?

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.

Can you test a fan blower resistor?

If you want to do a quick test of the blower resistor, you can check the resistance of each of the resistors with a multimeter as follows: set the tool to read ohms (a measurement of resistance) and connect one of its probes to the common output terminal of the resistor.

Is there a fuse for blower resistor?

A fuse is often located on the resistor board. The fuse only protects the low and medium blower speeds. High speed will still work if the resistor fuse is blown.

How do I know if my blower fan relay is bad?

One of the first symptoms of a problem with the blower motor relay is a blower motor that does not function. As the relay is the switch that supplies current to the blower motor, if it fails internally, then power may be cut off from the blower motor circuit causing the motor to no longer function.

How many ohms should a blower motor resistor have?

How Many Ohms Should A Blower Motor Have? A good blower motor is expected to read over 0.5 Ohms.

What causes blower motor resistor failure?

In most cases, the blower fan resistor is failing either due to overheating or corrosion. If the blower fan fails, your car will not blow any forced air. However, sometimes the problem can be with the blower motor itself. This is especially apparent when you have replaced the blower fan multiple times.

Should I replace both blower motor and resistor?

The heater blower motor resistor can often go bad because of a bad heater fan, and therefore you often have to replace both the heater blower resistor and the fan.

Can you repair blower motor resistor?

The average cost to replace the blower motor resistor at a repair shop is between $44 and $55 in parts and $70 in labor costs, for a total cost of around $114 to $125. What is this? On the other hand, you can easily fix the blower motor resistor at home in about an hour (even if you're a beginner) and for around $70.

How many ohms should a fan motor read?

A good motor should read less than 0.5 ohms. Any value greater 0.5 ohms indicate trouble with the motor.

Can a bad blower motor resistor cause no AC?

If the airflow from the vents is weak… A damaged blower motor resistor will work on one fan speed which may not be enough to keep the inside of your car cool or warm enough.

How do I test a blower fan relay?

Connect a test light or multimeter to the ground (black lead). Turn the ignition key to the on position (engine off), and remove the relay. Using the probe, test all terminal sockets in the relay connector. Two of the four should have power.

How do I reset my blower motor?

Follow these simple steps: First, turn off the power supply to the furnace by turning off the breaker in the circuit box. Locate the reset button on the furnace and press it to reset the furnace. It is usually located inside the blower compartment on the side of the blower motor.

How do you reset a blower motor?

How to Find and Reset your Furnace Motor Blower

Step 1: Turn off the power to the furnace.
Step 2: Remove the blower compartment cover. ...
Step 3: Make sure the blower is completely cooled off. ...
Step 4: Locate the reset button. ...
Step 5: Press the button in (assuming that this is your issue and that the button has popped).

Where is the blower motor fuse located?

The blower motor fuse is located in a small fuse box just next to the passenger.

Is there a fuse that controls the blower motor?

If the fan doesn't work, before pointing the finger at the blower motor, check fuses for the motor to make sure they're still good. Many vehicles have two fuses for the blower motor, one in the interior fuse block and the other under the hood. The blower motor is usually under the dashboard on the passenger side.

How do you diagnose a blower motor problem?

If the blower motor isn't running you should:

Use voltmeter or ohmmeter to check for a blown fuse. If you find one, replace it.
Start car and see if blower motor works.
If the circuits are in good repair but the blower motor keeps blowing fuses, replace the blower motor [source: You Fix Cars].

How can you tell if a resistor is bad?

If the resistor is fine, the multimeter will show its value in Ω, kΩ, or MΩ. However, if the resistor is bad or damaged, the multimeter may display 0 or 1. If the value 0 is displayed, the resistor is damaged, and the current can't pass through.

What voltage should a blower motor be?

A blower motor should receive between 12 and 24 volts of power in order to operate properly. If the voltage is too low, the motor will not be able to start or run properly. Too much voltage can damage the motor.