1. Preparation:
* Safety First: Disconnect the negative battery terminal to prevent accidental shorts.
* Gather Tools: You'll need a variety of tools, likely including:
* Screwdrivers (Phillips and possibly flathead)
* Socket wrench set (metric)
* Possibly panel removal tools (plastic pry tools to avoid scratching the interior)
* Pliers (needle-nose might be helpful)
* New power window motor (ensure you get the correct one for your specific door – front or rear – and year)
* Consult a Repair Manual: A Haynes or Chilton repair manual specific to your 1991 Chevy G20 is highly recommended. These manuals provide detailed diagrams and instructions tailored to your vehicle.
2. Door Panel Removal:
* Interior Panel Removal: This is usually the most challenging part. Start by removing any visible screws holding the interior door panel in place. These are often hidden under trim pieces or armrests. Use your panel removal tools carefully to pry the panel away from the door. Be gentle to avoid breaking the clips. The panel typically comes off in sections. Take pictures as you go to help with reassembly.
* Disconnect Electrical Connectors: Once the panel is off, you'll need to disconnect the electrical connectors for the power window switch, and possibly the lock and mirror controls (if they are integrated into the door panel assembly).
3. Window Regulator Access:
* Remove Window Regulator (Possibly): In some cases, you might need to remove the entire window regulator assembly to access the motor. This often involves more screws and potentially some linkage disconnections. Your repair manual will detail this.
* Locate the Motor: Once you have access, you should be able to see the power window motor. It's typically attached to the window regulator mechanism.
4. Motor Replacement:
* Disconnect the Motor: Disconnect the electrical connector to the motor.
* Remove the Old Motor: Depending on the design, the motor may be secured with screws or clips. Carefully remove it.
* Install the New Motor: Install the new motor, ensuring it's securely attached and aligned correctly. Reconnect the electrical connector.
5. Reassembly:
* Reassemble the Window Regulator (If Removed): Reinstall the window regulator (if you removed it) and reconnect any linkages.
* Reinstall the Door Panel: Carefully reinstall the door panel, making sure all the clips are properly engaged and all the screws are tightened.
* Reconnect the Electrical Connectors: Reconnect the electrical connectors for the power window switch, lock, and mirror controls.
* Test the Window: Reconnect the negative battery terminal and test the power window to make sure it operates correctly.
Important Considerations:
* Variations: The exact procedure can vary slightly depending on the specific trim level and options on your 1991 Chevy G20.
* Window Safety: Be cautious when working with the window to avoid damaging it. You might need to manually support the window during the repair.
* Clips and Fasteners: Keep track of all screws, clips, and fasteners during disassembly, as they are often easily lost.
Strongly recommend using a repair manual. Attempting this without one significantly increases the risk of damage or improper installation. If you're not comfortable performing this repair yourself, take it to a qualified mechanic.
