New sod is temperamental and easy to damage until it establishes its roots. It can be damaged by two much water, too little water, fungus, weeds and a variety of other factors. If your sod is literally dead, there's nothing you can do with it, but generally sod that is turning brown can be revived. Follow the care instructions provided by your sod dealer and you should bring your sod back to health.
Water the sod according to the instructions your sod company gave for the type of grass in your region. Generally, you should water about 3 times daily for between 10 and 15 minutes for the first week, then taper down over the next week or so.
Inspect your backyard for pooling water. If water is pooling on the surface where you have brown or unhealthy looking sod, decrease watering in that area
Spray any damaged spots with a blue-grey colour with a garden hose. These spots are sunburned, and need more water. Soak these spots with a hose every time you water your lawn.
Stick a screwdriver or similar long, skinny tool into a green, healthy corner of your sod. Next, stick it into a spot where the sod is brown and dead-looking. If the screwdriver is easier to push into the green sod than the brown, the brown is suffering from underwatering. Spray it with a garden hose as you did with the blue grey spots. If the screwdriver will not go through it, peel back the square of sod and remove the rock from underneath. Add more dirt beneath the square to even the lawn out and replace the sod.
Treat the brown area of the lawn with a fungicide according to the manufacturer's direction if the screwdriver pushed through as easily as it did in green parts of the sod. Lawn fungus is usually the cause of brown spots if the sod isn't underwatered.
Install your sod as quickly as possible. The longer before the sod is rooted, the more dry and damaged it will become.