How do you test a blower motor on a heater?

Using a multimeter set on the Ohm scale, use the positive lead and test the black wire. To check the purple wire for current, use your ignition key and turn it to the run setting, turn the heater power to full power and set the multimeter to DC power. If your meter reads "no current" the motor is no good.

Regarding this, how do you test a blower motor?

How to Test a Blower Motor

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 fuse blows again, check for loose circuits.
If the circuits are in good repair but the blower motor keeps blowing fuses, replace the blower motor [source: You Fix Cars].

Also, why is there no air coming out of my car vents? Common reasons for this to happen: Blown fuse: Like many electrical units in your car, the ventilation system relies on a fuse for overcurrent protection. If the ventilation system's fuse blows, then the circuit will stop working, and there will be no power for the vents. Bad relay: A bad relay can also be responsible.

One may also ask, how do I know if my blower motor is bad?

Symptoms of a Bad or Failing Heater Blower Motor

Weak airflow from the vents. One of the first symptoms of a potential problem with the vehicle's heater blower motor is low airflow from the vents.
Fan only blows at certain speeds. Another symptom of a bad or failing heater blower motor is a motor that only functions at certain speeds.
No air from the vents.

Is there a fuse for the blower motor?

The blower motor is powered by a fuse-like device called a relay. If your heater or air conditioner does not blow air through the vents, this could indicate that the blower motor fuse has probably blown. While replacement is easy, the exact location of your blower motor fuse may vary from vehicle to vehicle.

What can cause a blower motor to stop working?

In a situation where the motor doesn't work on any speed, the most likely causes are: a blown power supply fuse, a bad motor ground connection, bad motor speed control module or a failed motor. On all systems, a failed blower motor is least likely. Start by checking the blower fuse and HVAC controller fuse.

What does a bad blower motor sound like?

You might hear this as a noise coming from directly behind the vent, perhaps a light slapping, or a sudden pop before you notice a problem with airflow. Whirring noises might also result from a bad bearing in the motor. Does the noise change or increase when changing the fan speed?

How do I know if my blower motor resistor is bad?

Place one lead of the Ohmmeter on terminal 1 of the resistor. Place the other lead on terminal 2 and check against specifications. If this circuit is open, showing infinity on the Ohmmeter, the blower resistor must be replaced. Move the lead from terminal 2 to terminal 3 and check this reading against specifications.

How much does it cost to replace a blower motor?

The average cost for a blower motor replacement is between $363 and $394. Labor costs are estimated between $87 and $111 while parts are priced between $276 and $283. Estimate does not include taxes and fees.

What are the signs of a bad blower motor relay?

If you have faulty blower motor resistor you may experience low airflow coming from the vents even when the fan is all the way on high. In some cases bad blower motor resistor may not even turn the blower motor fan as a result your fan will not work at all and there will be no air coming from the vents.

Why does my blower motor work sometimes?

If little air is coming through the vents (hot or cold), then it could be because the blower motor for the fan or a switch or resistor that controls fan speed isn't working. Blower resistors are small parts that can become corroded or just burn out, and a new one often costs less than $50.

How long should an AC blower motor last?

15 to 25 years

How do you test a blower motor 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 much is a blower motor resistor?

The average cost for a blower motor resistor replacement is between $119 and $161. Labor costs are estimated between $47 and $60 while parts are priced between $72 and $101. Estimate does not include taxes and fees.

Can a blower motor get weak?

Weak Airflow from the Vents This is usually the first indication that you may have a faulty blower motor. If the airflow coming out of the vents is weak, it can mean that your blower motor is having a hard time pushing enough air through the ducts to achieve your desired temperature.

How many volts should a blower motor receive?

Typically it's done by measuring the voltage at the blower motor connector when it's turned on. If there is a voltage at the motor (at least 4-6 Volt at low speed and 12 Volt at high speed), but the motor doesn't run, the motor is bad or jammed.