Fan blower will run only on 4

The fan is located behind the glove box, above the passengers feet. The 2 most common failures are the blower motor and the blower resistor. This system is a switch to ground setup. Unplug the blower plug and see which wire is hot, it should always be with the key on. With the car running and the fan switch on, hit the blower with the palm of your hand. If it comes on, it is bad. the brushes wear out. Also you can unplug the resistor, and ground the output wire at the blower, or resister. to see if it works.

You will need to replace the blower motor speed control module/resistor, it is burned out. it is located next to the blower motor.

Blower Motor Control Processor is probably bad , these go out all the time . The blower motor is computer controlled . Your's works just like the one in this video .
HVAC Blower Motor Circuit

Hi!!
When the Blower Motor Resistor (controls blower speeds) goes bad, the blower motor works only on HIGH SPEED. REPLACE IT.
BLOWER MOTOR RESISTOR Removal & Installation

• Disconnect negative battery cable.
• Remove right lower instrument panel insulator panel.
• Disconnect blower resistor connector located behind right side of dash.
• Remove blower resistor screws and blower resistor.

To install, reverse removal procedure
Good Luck!! A HELPFUL - 4 THUMBS - rating for this solution would be greatly appreciated. Thank you for using FixYa!!

hi the fault is most properly in the fan controller it is not uncommon that the fan only works in the number four setting change the fan controller and you will be all right. Hans

check the fuses and relays goodluck

the blower not working on settings 1-3 is the blower motor resistor. this limits the power provided to the blower motor itself to change the speed. at setting 4 it is getting full power. since it quit on 4 also, i would still say the resistor needs to be replaced first, then see if the blower comes back. you may also need a blower motor. if you have a voltmeter you can just turn the switch to 4 and see if the motor is still getting 12 volts. if it is and doesn't run, it needs a blower motor too. if it's not, then its just the resistor

Check the blower motor resistor pack.
This is usually located in the blower motor ducting in the air stream.

when it wont work leave the truck on and open the hood on the passager side the blower motor is there gently tap it if its start change the blower motor that the fast way to do it im sure its our motor good luck pierre p.s dont forget to rate me after you tryed what i told you

Your blower resistor is bad. It is mounted under the passenger side dash behind and to the left of the blower motor. These things burn out short out causing the fan to run constantly and then they just fry and shut down the fan. It is a hard little ****** to get to and you need 1/4 inch ratchet, 6 inch extension a 1/4 inch universal joint and a 5 mm shallow socket and lots of patients. LOL