* Weak Motor: As the motor ages, its internal components can become more susceptible to temperature changes. When cold, the lubricant may thicken, making it harder for the motor to turn. Warming up thins the lubricant, allowing it to function.
* Faulty Wiring or Connections: Cold temperatures can exacerbate problems with corroded or loose wiring connections within the door harness. The connection might make intermittent contact, only functioning reliably when the components are warmer and expand slightly.
* Frozen Mechanism: While less likely in just "cold" weather, moisture can sometimes freeze within the window regulator mechanism itself, binding it up and preventing movement. This would be more probable with very cold, damp conditions.
* Lubricant Issues: The lubricant used in the window regulator might have degraded over time. When cold, this degraded lubricant becomes extremely thick and resists movement, only becoming usable once warmer.
* Resistor in the Motor (Less likely): Some motors have internal resistors that can be affected by temperature. This is less common than the above issues.
Troubleshooting Steps:
1. Check the obvious: Make sure the power window switch isn't the problem. Try all window switches to eliminate that as a variable.
2. Listen for sounds: When attempting to operate the window, listen closely at the door. Unusual sounds (grinding, clicking, humming) can pinpoint the source.
3. Inspect the wiring: Carefully inspect the wiring harness in the door for any signs of damage, corrosion, or loose connections. Pay particular attention to the connections at the motor and switch.
4. Lubrication (Use caution): If you're comfortable doing so, you could try applying a small amount of silicone-based lubricant to the window regulator mechanism (after disconnecting the power). This is a temporary fix and might not address the root cause. Do not use WD-40.
Recommendation: If you're not comfortable diagnosing and repairing electrical issues, it's best to take your Windstar to a qualified mechanic. They have the tools and expertise to properly diagnose the problem and perform the necessary repairs. Ignoring the issue could lead to more serious damage and higher repair costs down the line.
