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 do I know if my blower motor 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.
Can you bypass 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 do you test a blower motor with a multimeter?
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.
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 does it cost to replace 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.
What causes a blower motor resistor to go 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.
Why is my blower motor not 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.
Why is the blower in my car not working?
The most common reason why your blower motor won’t work on any speed is that you have a bad or blown a fuse. A fuse is a small wire inside of a connector that is used to protect the motor itself from a surge of electricity.
How do I know if my blower motor has power?
Check for power at the motor itself. Using a test light or a multimeter set on volts, unplug the blower motor. Keeping the black lead on a good ground, usually a bolt on the engine block, and the blower switch turned on, use the red lead to probe the plug that usually attaches to the blower motor.