The blower motor resistor is
responsible for controlling the blower motor speed
. In the past, this was done by varying the voltage supplied to the blower motor. In newer applications, the blower motor resistor is actually a solid state module that sends a varied signal to the blower motor.
What are the signs of a bad 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 happens when blower motor resistor goes bad?
If the resistor shorts or fails,
it may cause the blower motor to remain stuck on one fan speed
. The heating and air conditioning systems may still function at one speed, however the resistor will have to be replaced in order for full functionality to be restored.
Is my blower motor or resistor bad?
If the airflow from the vents is weak…
If you try to increase the air pressure and you feel no difference in the pressure blowing, then your
blower motor resistor may be failing
. 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.
Can you bypass a 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.
How much does it cost to replace a blower motor resistor?
The average cost for a Blower Motor Resistor Replacement is
between $108 and $137
but can vary from car to car.
Can a blower motor be repaired?
Blower Motor Replacement: When Good Parts Go Bad. … There are a number of things that can go wrong with your heating system, but if the air stops blowing altogether and the same is true on cold air settings, a blower motor replacement is likely in order. The good news is that it's
a fairly straight forward repair
.
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.
Can you test a blower motor 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.
What does a bad blower motor sound like?
A working blower motor will operate smoothly and inaudibly. A defective blower motor will make a continuous sound noticeable by the passengers in the vehicle. It can manifest as
a knocking, whirring, clunking, vibrating, squealing, or whining noise
that persists until the blower motor is replaced.
How long does a blower motor last in a car?
For the most part, the heater blower motor on your car is supposed to
last as long as the actual vehicle does
. Due to the harsh conditions that this blower motor has to operate in, it will usually end up having repair issues. There are a variety of problems that the blower motor may have that will render it useless.
How much does it cost to replace a blower motor?
Cost to Replace Central or Forced Air Blower Motor
Replacing a blower motor costs
$450 on average
with a typical range of $250 to $800. With a warranty, you might pay as little as $150 for labor alone. For high-end models, like those with large motors or access issues, you might pay as much as $2,000.
How do you test a blower motor resistor?
Blower Motor Resistor Testing
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.
Can you bypass a resistor?
A wire in the left circuit is shorting the 100Ω resistor.
All current will bypass the resistor
and travel through the short. The voltage across the 100Ω resistor is going to be zero.
What does a final stage resistor do?
The final stage (or blower motor) resistor
controls the speed of the blower motor in your heating & air conditioning system
. Faulty resistors can cause a list of erratic issues, from the fan running when the car is off, to only having one fan speed available.
