Thanks to Graycenphil for the detailed instructions.
I own a 2014 Leaf.
I was away for less than a week, and a mouse got all the way in into the ventilation blower, leaving droppings, acorn skins and leaves. My quiet fan was suddenly rattling loudly.
Following the given steps, I was able to get to the fan, and cabin air filter, and vacuum all the debris left by the critters. Now My fan is quiet again.
These are the steps to get to the fan:
First step is to remove the glove compartment.
1. Remove the plastic panel under the glove compartment pulling downwards. It looks like this:
2. Remove 4 screws under the glove compartment:
3. Open the glove compartmet. Remove 2 screws inside:
4. Remove 4 screws across the top:
5. Pull glove compartment towards the front. It is held in place by 1 plug on the left, and three on the right. This is how the glove compartment looks when removed:
6. A circuit module is in the way. By removing these two screws, it can be moved down. No need to disconnect any cables:
This how it looks when the circuit module is out of the way:
7. This is the blower fan. Disconnect the connector at the right. It has a latching tab:
8. Remove the fan by pressing on the tab located at the top, and rotating to the right a quarter of an inch or less. The fan assembly comes out effortlessly:
9. Clean the fan as needed. I also vacuumed the fan cavity:
10. Below the fan cavity is the cover for the cabin air filter. Open it from below and extract the filter. I also had mouse droppings and debris. I also vacuumed the cavity where the air filter sits:
Do everything is reverse to put all back together. As mentioned by Graycenphil, the fan cable might be in the way:
Tuck it away temporarily as shown: