How do you test a blower motor resistor?
How do you test a blower motor resistor?
NOTE: To see actual resistance specifications for the continuity test of this test section, go here: Blower Resistor Continuity Specification Tables. Disconnect the blower motor resistor from its connector and remove it from its location. Visually inspect the blower motor resistor block and connector for burn damage and severe corrosion.
How does a blower motor resistor control the fan speed?
The blower motor resistor controls the fan speed of the blower motor and the resulting change in air pressure produced by the movement of the blower fan. It accomplishes this by regulating the electric current that powers the motor.
What to do if your blower resistor Burns?
Look for obvious signs of corrosion and burns from overheating. If you see signs of overheated connectors, replace the blower resistor and its connector, but again, you must splice the wires right, or you’ll have problems at the splice later on.
Where is the blower motor resistor on a Dodge Dakota?
This tutorial will help you test the 2001-2004 Dodge Dakota and Durango blower motor resistor in a step-by-step way. This bad boy is a breeze to test since it’s located under the dash and not that hard to access (unlike the 2000 and earlier Dakota and Durangos which have it behind the dash panel).
Where is the resistor on a blower motor?
Because resistance creates heat while current is flowing, the blower resistor is mounted in the duct near the blower motor so the resulting airflow will keep the resistor cool.
Look for obvious signs of corrosion and burns from overheating. If you see signs of overheated connectors, replace the blower resistor and its connector, but again, you must splice the wires right, or you’ll have problems at the splice later on.
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.
How is the speed of the blower motor controlled?
On climate control systems without automatic temperature controls, the blower motor speeds are controlled by a switch wired to a stepped resistor that usually includes a thermal fuse.
When a switch, a resistor, and a load are wired in series, the resistor “drops” some of the voltage passing through it, effectively reducing both current flow and voltage at the motor. A voltmeter connected to both ends of a resistor while current is passing through it to a load will measure the amount of voltage being “dropped” by the resistor.
When does the blower resistor need to be replaced?
If this circuit is open, showing infinity on the Ohmmeter, the blower resistor must be replaced. Move the lead from terminal 3 to terminal 4 and check this reading against specifications. If this circuit is open, showing infinity on the Ohmmeter, the blower resistor must be replaced.
How do you test a resistor in a circuit?
An attempt to measure a resistor that is still connected to the circuit can yield an incorrect calculation, as part of the circuit might also be measured. Disconnect one end of the resistor from the circuit. It does not matter which end of the resistor is disconnected. Disconnect the resistor by pulling on the resistor.
What should I do if my resistor is black?
Inspect the resistor. If the resistor shows signs of blackening or charring, it may be damaged by excess current flow. A resistor showing blackening or charring should be replaced and discarded. Read the resistor value visually. The resistor value will be printed on the resistor.
How do you know if your blower resistor is bad?
Another common symptom of a faulty blower motor resistor is a a blower motor that does not function on certain settings. If the blower motor resistors’ internal components fail it may cause the blower motor to malfunction, or not function at all on one or more of the settings.
What are the symptoms of a bad 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 is the purpose of a blower motor resistor?
The blower motor resistor is an electrical component that is a part of the vehicle’s heating and air conditioning system. It is responsible for controlling the blower motor’s fan speed. A failed blower motor resistor can cause issues with the operation of the entire heating and air conditioning system.
Is there a way to test a blower motor?
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. Move the lead from terminal 2 to terminal 3 and check this reading against specifications. Move the lead from terminal 3 to terminal 4 and check this reading against specifications.
