Put new blower motor and resistor in my 91 dakota and it keeps melting heater fuse. how do i fix

The problem was the motor. Replace the blower motor and resister and it should be fine.

If the blower motor resistor is experiencing repeated failure, the blower motor is likely drawing too much current. Excess current draw from the blower motor will cause the resistor to burn out. The blower motor in your truck has a resistor block with multiple resistor wires.
Jun 21, 2023

Why Does the Blower Motor Resistor in My Dodge Dakota ...

More here

https://www.google.com/search?q=2004+Dodge+Dakota.+It+keeps+blowing+the+blower+fan+resistor

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Can you measure and VOLTAGE across the resistor?

Here is a GREAT Link (in my estimation):
How To Test The Blower Motor Resistor 2001 2004 Dakota Durango
Yes it's for a DURANGO but the process may help you!

Joe, have you seen THIS link?
2003 dodge dakota heater schematic Google Search

And THIS YOUTUBE?
Dodge Dakota Durango Blower Motor Resistor Wiring Diagram

Also there is this possibility:


That link is here (yes ~ again it's for a DURANGO, but the help may be here)!

Connector to blower resistor DodgeForum com

Anthony

It's probably the blower motor resistor. It can overheat and burn out, often melting the connector so the connector cannot be separated. See the linked YouTube video for information on replacing the resistor, and connector if necessary.
Dodge Dakota Durango Blower Motor Resistor Replacement

Hi. If the brushes are worn or have worn in the past to the point where there is damage to the rotor commutator, that could blow fuses for you.

Are you saying the fuse doesn't blow when the heater is on "high" and the resistor disconnected?

should be just above the blower motor. You will need to remove the glove box door to gain access.

I’m happy to assist further over the phone at https://www.6ya.com/expert/jeremy_d728a59f986299fa

Your Blower motor is going bad drawing to much amperage if you keep replaceing the fuse you can melt the connector where it plugs into the motor and make it harder to repair because now you have to repiar the wiring. You should also replace the Blower motor resistor when you replace the Blower motor . They work together and somtimes when the blower motor goes bad it damages the resistor internally and fails right after you put the new motor in .

The blower resistor will burn and smell without blowing a fuse

It could be the blower motor resistor module.It is located on the passengers side next to the blower motor.Make sure the connections are not melted.Because if they are you will have to replace them also.Hoope this helps.Good luck.

Yes new blower and regulator

replace the resistor that should fix it