1. Power Issues:
* Fuse: Check the fuse box for a blown fuse related to the power windows. Your owner's manual will show you which fuse is responsible.
* Wiring: Look for broken, frayed, or corroded wires in the door harness (where the wires enter the door) and along the window regulator's path. This is a common problem area, especially if the door has been opened and closed many times. Inspect both the positive and negative wires.
* Switch: The power window switch itself could be faulty. Try the other window switches to see if they work. If only one window is affected, the switch is a prime suspect. You can try spraying some electrical contact cleaner into the switch, but replacement might be needed.
* Relay (Less likely): Some vehicles use relays for power windows. Check your owner's manual or a wiring diagram to see if your Blazer uses a relay and test it if necessary. This is less common on older vehicles.
* Battery: A weak battery can sometimes affect power-hungry accessories like power windows. Check your battery voltage.
2. Mechanical Issues (within the door):
* Window Regulator: This is the most common mechanical failure. The regulator is the mechanism that raises and lowers the window. It can have broken cables, a stripped gear, or a seized motor. This requires removing the door panel to inspect.
* Window Motor: The motor itself could be burned out or jammed. Again, you'll need to access the motor by removing the door panel.
* Window Tracks: Dirt, debris, or damage to the window tracks can prevent the window from moving smoothly. Clean the tracks thoroughly.
3. Other Possibilities:
* Stuck Window: Something may be jammed in the window track or preventing the window from moving. Check carefully.
* Broken Window: Check for any cracks in the glass, which may have caused the window to bind.
Troubleshooting Steps:
1. Start with the simplest: Check the fuse first. This is the easiest and cheapest fix.
2. Inspect the switch: Does the switch feel loose or make clicking sounds?
3. Listen carefully: When you operate the switch, do you hear any motor noise? If not, the problem is likely electrical or the motor itself. If you hear a clicking sound but no movement, it could be the regulator or motor.
4. Visual Inspection (Door Panel Removal): This is the most likely step needed for diagnosis. Removing the door panel (requires removing screws and potentially unclipping panels) allows you to visually check the regulator, motor, and tracks for damage or obstructions. Many online resources offer tutorials for your specific year Blazer. Be extremely careful during this process – take pictures before you start to aid reassembly.
If you're not comfortable doing this yourself, take your Blazer to a qualified mechanic. They will have the tools and expertise to diagnose and repair the problem efficiently.
