* Broken or Stripped Gears: The most probable cause. The electric motor drives gears that move the seat. These gears can become stripped, broken, or worn out over time, preventing movement even if the motor is functioning. This is especially likely if the seat has been used heavily or subjected to rough treatment.
* Binding or Obstructions: Something might be preventing the seat from moving. This could include:
* Debris: Small objects lodged in the tracks.
* Worn Tracks: The tracks the seat slides on could be damaged, causing binding.
* Cable Issues (if applicable): Some seat adjustment mechanisms use cables. These could be frayed, broken, or jammed.
* Internal Mechanical Failure: There are other internal components besides gears that could fail. This is harder to diagnose without disassembly.
* Worn-out Motor: Although less likely if you hear the motor running, it's possible the motor is weak or failing, not generating enough power to overcome the friction within the mechanism. A faint, struggling motor sound might be a clue.
* Switch Problem (less likely): While you hear the motor, it's *possible* the switch is sending a weak signal, not providing enough power to the motor to fully engage, although this is much less probable than the other issues.
Troubleshooting Steps (in order of easiest to hardest):
1. Check for Obstructions: Inspect the seat tracks for any debris or objects that might be preventing movement. Try gently moving the seat by hand (carefully!) to see if there's any significant resistance.
2. Listen Carefully to the Motor: Does the motor sound weak or strained? A strong, consistent hum points toward a mechanical problem within the seat, while a weak or intermittent sound might suggest motor failure.
3. Inspect the Tracks: Examine the tracks carefully for damage, bending, or signs of wear.
4. Professional Help: If you're not comfortable disassembling the seat, this is the best next step. A mechanic can diagnose the specific problem and repair or replace the necessary components. Attempting to repair this yourself can be challenging, as the seat mechanism is usually complex.
In short, while the motor running is a good sign that the electrical side isn't the primary problem, a mechanical failure within the seat itself is the most likely cause. Focus your troubleshooting on identifying any mechanical obstructions or damage.
