You have one of two things that are wrong. One you can do. Take the cover off of the fuse box. Then take off the 6 phillips screws that hold the outer cover on. Take off the cover and look to the rear. You will see 2 relays with fuses in the top. Replace the 15a relay with a 20a. If this does not fix it, you will need a tech. The resistor could have burned up near the drier bottle. This resistor helps the fan to run on low speed, but produces heat. The heat will, over time, burn the wire and the resistor up. A tech will have to run a new wire and replace the resistor.
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