What happens when a blower motor resistor is bad?

What happens when a blower motor resistor is bad?

Without any power, the motor won’t run. As a result, the blower fan stays still and silent, and no air blows out of the vents. There are instances where a bad resistor will prevent the current from reaching the blower motor altogether. Resistors have it rough.

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 a step resistor used in a fan?

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. Because lower voltage means lower current delivered to the fan, the stepped resistor circuit can be used to control fan speed.

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.

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.

What happens when you replace the resistor on a Sebring?

Re: I replaced resistor and the blower still does not… You can’t post conmments that contain an email address. 2000 chrysler sebring had battery light on yesterday. Door won’t even lock with the key. Cleaned the battery cables and it started first thing this morning.

Where are the fuses on a blower motor?

Check fuses 10 & 11 in the underdash fusebox. 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.

Without any power, the motor won’t run. As a result, the blower fan stays still and silent, and no air blows out of the vents. There are instances where a bad resistor will prevent the current from reaching the blower motor altogether. Resistors have it rough.

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.

Why does my blower motor make a squeaking noise?

This may be a sign of a faulty blower motor. As you might know, these have electric motors in them that wear out over time and will begin to make squeaking or grinding noises as the bearings begin to wear out. The electrical contacts may also wear out causing the motor to fail.

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.