More than likely the blower motor is bad or a resistor is bad. But you need to check it out first. There are 2 fuses to check. A 20 amp A?C FAN fuse in the left fuse box and a 25 amp BLO fuse in the right fuse box. If those are good, unplug the blower motor connector. hook a test light up to the 2 wires for the blower motor and turn the fan on and cycle through all speeds. The test light should light up at each speed and get brighter the faster the speed is. If it does, Replace the blower motor. If not, there is a resistor behind the blower motor that is probably bad. it has 7 wires at the connector for it and 2 wires going to blower motor. To test it, hook a test light up to the purple wire and turn the blower to the #4 setting. If you have power there. the resistor is bad. Let me know if need any more help or don't under stand a step. Or need help with a repair.
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