Where is the blower relay resistor located

It is on the passenger side underneath the dashboard. Remove the cover first and you should see your blower. There is one screw that holds the blower vent to the blower. Remove that . Now you should see where the cable plug to the resistor. Anyhow, here is a great site that will show you more of the detail. Also some great info about your blower right here. About .com has a great image I attached it so you can get better detail. I hope this helps and good luck to you.

On the 2000 Dakota, the blower motor resistor is located under the center of the dash against the firewall. The dash does not have to be completely removed to access it, but it does need to tilted back in the brackets about 6 inches. Expect at least 2 hours for labor, it took me 4 for the entire disassemble, part exchange, and reassemble process. There is a PDF out there that explains the dash removal process.