Because its location can vary slightly depending on the specific engine and options, you'll likely need to:
1. Consult your owner's manual: This is the best place to start. The manual will show a diagram or explain the location.
2. Visually inspect the lower driver's side of the engine: Look for a heavy-duty cord and a connector that might be plugged into the engine block itself. Be cautious around hot components if the engine is warm.
3. Feel around (carefully): If you can't see it immediately, carefully feel around the lower driver's side of the engine block, paying attention to any thicker cords that look out of place.
Important Note: If you can't locate it after a reasonable search, it's possible your specific G5 model did not come equipped with an engine block heater.