Here's what you should do:
1. Locate the Blower Motor Resistor: This is usually located behind the glove box, under the dashboard, or sometimes even in the blower motor housing itself. Consulting a repair manual specific to your 1999 Dodge Caravan will be invaluable in finding its exact location. A wiring diagram will also be helpful.
2. Inspect the Resistor: Once located, visually inspect the resistor for any obvious signs of damage, such as burning, melting, or loose connections.
3. Test the Resistor (Optional but Recommended): If you have a multimeter, you can test the resistor's resistance values to confirm it's faulty. Again, your repair manual will provide the correct resistance values for each speed setting. If the readings are significantly off or show an open circuit, the resistor needs replacement.
4. Replace the Resistor: If the resistor is damaged or tests faulty, replace it with a new one. Make sure to get a replacement that's specifically designed for your 1999 Dodge Caravan. You can find these at most auto parts stores. The replacement process generally involves removing the old resistor and plugging in the new one – but again, your repair manual will provide step-by-step instructions.
Other Less Likely Possibilities:
* Blower Motor Issues: While less common if high speed works, a failing blower motor could also contribute. This is less likely as the motor is still functioning on high.
* Wiring Problems: Damaged or corroded wiring between the resistor and the blower motor or the switch could also be a factor. Inspect the wiring carefully for any breaks or corrosion.
* Switch Problems: A faulty blower motor switch is also possible, although less likely if the high speed works.
Important Considerations:
* Safety First: Disconnect the negative battery terminal before working on any electrical components in your vehicle.
* Repair Manual: A repair manual specific to your year and model of Dodge Caravan is highly recommended. It will provide detailed instructions, diagrams, and specifications to help you safely and effectively complete the repair.
If you're not comfortable working on your vehicle's electrical system, it's best to take it to a qualified mechanic. Replacing the blower motor resistor is usually a relatively straightforward repair, but improper work could lead to further damage.
