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 the highest speed setting (4 or 5) and doesn’t work at low speeds. In some cars, a failed blower motor resistor can cause a heater fan to stop working completely.
How do I know if my blower motor or resistor is bad?
Symptoms of a Bad or Failing Heater Blower Motor Resistor
- Blower motor stuck on one speed. A common symptom of a faulty blower motor resistor is a blower motor that is stuck on one setting. …
- Blower motor does not work on certain settings. …
- No air from the vehicle’s vents.
What are the symptoms of a bad blower motor?
Here are just a few of the signs that your blower motor is going bad.
- Weak airflow. This is one of the first signs of a bad blower motor that people tend to notice. …
- Noises. Have you noticed any unusual noises coming from your vehicle’s HVAC system? …
- Smoke or smells.
Should I replace blower motor and resistor?
We do suggest that you replace the resistor at the same time. It may not be critical, but this will keep the system more uniform. The issue may even be related to the resistor. If you know that it is not related to the issue, then you do not have to replace it.
How do I test a blower motor resistor?
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 can you tell if a resistor is bad?
Your meter will read it as open circuit (infinite ohms). Or maybe it’s a 0.1 ohm current sensing part. Your meter will read it as a short circuit. If it’s a larger resistor with leads and it looks and smells burnt, assume it’s bad.
Why does my blower motor resistor keep burning out?
Trent, one of the biggest reasons for blower motor resistors to have shorten life is actually because of faulty blower motor drawing too many amps, some times melting wires/plugs, heating up resistors shortening their life.
How do I know if I need a new blower motor?
What Are Signs Your Blower Motor Needs to Be Replaced?
- Poor or Airflow from Air Vents. This will be the first and most obvious sign your blower motor has a problem. …
- No Airflow At All From Vents. …
- Skyrocketing Energy Bills. …
- Strange Noises When You Turn on the Heat. …
- Overheating Blower / Weird Smells.
Do blower motors get weak?
Weak airflow is a sign of blower motor failure. This part wears out eventually, meaning its fans can no longer push adequate amount of air out the vents or through window defrosters.
Can you fix a blower motor resistor?
The resistor module is easy and inexpensive to replace. It’s then typically installed in the ductwork, near the car blower—either under the dash or under the hood. … Remove the screws, and swap out the resistor module. Reconnect the electrical connector and you’re car heater blower motor is back in business.
Can a blower motor resistor be bypassed?
Blower resistors are made of several resistors with different resistances. … 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.
How much resistance should a blower motor resistor have?
According to the service manual, it must be around 4-5 ohms. In our case the ohmmeter shows open circuit, which means the resistor has failed. Sometimes, a blower motor resistor might fail due to problems with the blower motor itself.
How much is it to replace a blower 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.