1. Fuses:
* Locate the fuse box: Your Caravan likely has two fuse boxes – one under the hood and one inside the vehicle (often under the dashboard). Consult your owner's manual to locate them and identify the fuses related to the power windows (there might be separate fuses for the front and rear windows, or even a single fuse for all windows).
* Check the fuses: Carefully inspect the fuses for any signs of damage (blown filament). Replace any blown fuses with fuses of the *same amperage*.
2. Window Switch:
* Test the switch: Try all the window switches. If only one vent window is malfunctioning, the problem is likely localized to that switch. If all vent windows are affected, the issue may be elsewhere. Sometimes, the switches can become faulty internally, even if they appear fine externally.
* Clean the switch: Try cleaning the switches with contact cleaner (electrical contact cleaner is best). This can sometimes resolve issues caused by dirt or corrosion.
3. Wiring:
* Check wiring connections: This is more involved and requires some electrical knowledge. Inspect the wiring harness leading to the window motors and switches. Look for any broken, frayed, or loose wires. Disconnecting and reconnecting connectors can sometimes help.
* Look for chafing: Wiring harnesses can sometimes rub against sharp edges, causing damage. Examine the wiring carefully for signs of chafing or abrasion.
* Continuity test (advanced): If you're comfortable with a multimeter, you can test the continuity of the wiring between the switch, the fuse box, and the window motor. This would require you to consult a wiring diagram for your specific Caravan model.
4. Window Motor:
* Listen for noise: When you try to operate the vent windows, do you hear any clicking or humming sounds? A clicking sound often indicates a problem with the motor or the switch. A humming sound usually points to the motor, indicating it's trying to work but is struggling.
* Access the motor (difficult): Accessing the motor will require removing the door panel. This is not a simple task and may require some mechanical aptitude. Once accessed, visually inspect the motor for any obvious damage.
5. Relay (Less Likely):
* Some systems use a relay to control the power to the windows. While less common, a faulty relay could be the culprit. You would need to consult a wiring diagram to identify the relay.
6. Master Window Switch (if applicable):
* Some vehicles have a master window switch that controls all the windows. If this is malfunctioning, all the windows may be affected.
Important Considerations:
* Owner's Manual: Your owner's manual is your best friend. It will have diagrams of the fuse boxes and potentially some troubleshooting tips.
* Repair Manual: A repair manual specific to your 1999 Dodge Caravan will provide detailed information on wiring diagrams, component locations, and repair procedures.
* Professional Help: If you're not comfortable working with car electrical systems, it's best to take your Caravan to a qualified mechanic for diagnosis and repair. Incorrect wiring can cause further damage.
Start with the simplest steps (fuses and switch cleaning) before moving on to more involved troubleshooting. Remember safety first – disconnect the battery negative terminal before working with the electrical system.
