Frequently Asked Questions - Heating and Air Conditiong

First, if you have an in-cabin microfilter, ensure that it is clean and functional and not backed-up by debris, which can retain water, causing the musty smell.

Next, with the Xterra running, and the A/C on with moderate fan (disable "re-circ" mode) - spray Lysol Disenfectant into the grille/openings on the windshield cowl, just below the bottom of the windshield. Apply a liberal amount, then shut down the truck and A/C and allow to sit for a while. Repeat if necessary.

The in-cabin microfilter passes all air when in A/C mode (whether external/recirc mode is selected) through a medium similar to an engine air cleaner. It removes most dust and pollen from the airstream.

They are under the front driver/passenger seats, and are difficult to see from glancing underneath. Open the door and look in from the side, they're black plastic and about 1/4" tall by 3" wide.

The in-cabin microfilter is installed behind the glove box, and should be replaced every six months. It comes in two identical pieces - filter elements. The instructions that come with the replacement filters is for a Frontier and are incorrect. Instead, follow below:

You will need to remove four screws holding in the glove box and two additional screws for the metal latch. Remove the small black clip at the bottom of the two filters to remove and re-install new filters. Reverse removal procedure.