How does a blower motor resistor control speed?
How does a blower motor resistor control speed?
It uses resistance to control the speed of the blower motor. At high speed, the resistor is bypassed, and power comes directly from the switch. This illustration shows a typical blower resistor, specifications, and test procedures vary between different manufacturers. Place one lead of the Ohmmeter on terminal 1 of the resistor.
What should the voltage be on a blower motor?
If those are OK than backprobe the blower motor connector and check for power on terminal 1. Check terminal 2 for a variable voltage, this should be 12v with the fan control knob on off and 5v or full ground on full. If that checks out replace the blower motor.
How can I tell if my blower motor resistor is bad?
A repair manual can tell you where its location is in your vehicle’s make and model. Inspect the resistor visually. Look for obvious signs of corrosion and burns from overheating.
Can a broken motor switch stop a blower?
A broken blower motor switch can also stop the blower from changing to certain speed settings. If your blower motor cannot change to certain speeds, check both the resistor and the switch on your dashboard. The most common failure points are the resistor and the motor itself.
It uses resistance to control the speed of the blower motor. At high speed, the resistor is bypassed, and power comes directly from the switch. This illustration shows a typical blower resistor, specifications, and test procedures vary between different manufacturers. Place one lead of the Ohmmeter on terminal 1 of the resistor.
How can you tell if a blower resistor has failed?
With a DMM (Digital Multimeter – Ohmmeter function) remove the blower resistor and measure the resistance readings on the blower resistor module between pin 2 and pin 1 (should read 0 Ohms) then between pin 1 and pin 3 then 3 & 4 then 4 & 5 and see what they are reading to find out which one has failed.
If those are OK than backprobe the blower motor connector and check for power on terminal 1. Check terminal 2 for a variable voltage, this should be 12v with the fan control knob on off and 5v or full ground on full. If that checks out replace the blower motor.
What are the symptoms of a bad heater motor resistor?
Symptoms of a Bad or Failing Heater Blower Motor Resistor. 1 1. 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. The blower 2 2. Blower motor does not work on certain settings. 3 3. No air from the vehicle’s vents.
