Find the brake fluid reservoir / brake fluid tank and check fluid level
Hans Angermeier is an ASE certified Maintenance and Light Repair Technician and has produced over 100,000 videos showing drivers how to fix things on their cars. He has broad expertise on basic repair procedures covering the majority of cars on the road. Over the past 10 years, Hans has been focused on building CarCareKiosk, which is visited by millions of drivers each month.
Checking the brake fluid in your 2009 Nissan Maxima is easy and should be done once a month. On some Nissans, the owners manual suggests pumping the brake pedal 25 times before looking at the fluid level, be sure to check your owners manual to see if this applies to your 2009 Maxima. In addition to checking the brake fluid level, you want to look at the color of the brake fluid in your Maxima - if it is dark in color or it has been more than 2 years since you have changed it, you should consider having it changed - this will help make the internal components (which are expensive) last much longer.
If you need to add fluid to your Maxima, it is important to check your owners manual for the correct type to add - it likely be either DOT 3, DOT 4 or DOT 5, also known as silicone brake fluid. Be sure to discard bottles of brake fluid that are over a year old - brake fluid sucks the moisture out of the air and the water vapor in the fluid can quickly rust out the brake lines in your Maxima.