* Short in the window motor: This is the most common cause. Worn brushes, internal damage, or moisture inside the motor can create a short circuit, drawing excessive current and blowing the fuse. This is particularly likely if only one window is affected.
* Short in the wiring harness: Wires can chafe against metal parts, especially in the door area where they flex with the window movement. This chafing can cause the insulation to wear, leading to a short. Rodents chewing on wires is another possibility. Look carefully for damaged or frayed wiring in the door jambs and around the window regulator mechanism.
* Short in the window switch: A faulty window switch can draw excessive current, although this is less common than motor or wiring problems.
* Window regulator issues: A binding or seized window regulator can put extra strain on the motor, leading to a higher current draw and blown fuse. This is often accompanied by the window operating sluggishly or not at all before the fuse blows.
* Excessive moisture: Water intrusion into the door can corrode wiring and components, causing shorts.
Troubleshooting Steps:
1. Identify the specific blown fuse: Your owner's manual will show you the fuse box location and the fuse responsible for the power windows. Don't just replace it with another fuse of the same amperage. Find the *cause* of the problem!
2. Check the window motor: If only one window is affected, focus on that window's motor. You might hear unusual noises (grinding, clicking) when trying to operate it. Visual inspection for obvious damage is a good first step.
3. Inspect the wiring harness: Carefully examine the wiring harness in the door, paying close attention to areas where the wires bend and flex. Look for frayed wires, exposed copper, or signs of rodent damage.
4. Test the window switch: Try the switch on a different window. If the problem follows the switch, it's likely faulty.
5. Check for moisture: Inspect the door for signs of water damage or leaks.
Important Note: If you're not comfortable working with car electrical systems, it's best to take your Expedition to a qualified mechanic. Improperly repairing electrical problems can lead to more serious issues, including fire hazards. Replacing the fuse repeatedly without addressing the underlying short is a temporary fix at best and potentially dangerous.
