Look for any mortar (the porous, concrete-like material between your bricks) that has cracks, crumbles or missing parts. Also look for any loose, cracked or dislodged brick. Pay special attention to areas that border windows and door openings. Small cracks (1/4 inch or less) in the mortar aren't a problem, but they should be monitored every few months to make sure they aren't growing. Cracks that are larger than 1/4 inch, or damage that goes through both the mortar and the brick may be a sign of a more serious problem with your foundation, and you should contact a qualified home professional to inspect the problem.

Angie's How To Brick and Stone Maintenance
You've got brick and/or stone on the outside of your home, which means you never have to worry about rotting, fading or peeling (or the big bad wolf blowing your house down). It's also fire resistant and extremely durable. Once a year, follow these steps to make sure your brick and/or stone stand the test of time.
3 pros!
Weep holes are small holes in the exterior brick/stone that allow water to drain out rather than accumulate in the space between your walls and your brick. Look for these holes slightly above your foundation line and make sure they aren't clogged. Weep holes must be above the ground so that they don't become clogged with water or dirt, or become entranceways for pests. If your weep holes are clogged, or your foundation has shifted so that the weep holes are partially or fully submerged, contact a qualified professional foundation expert to repair the problem.
Any area where your brick/stone meets another building material (window sill, brick, vinyl, etc.) is vulnerable to moisture and will generally have a layer of caulk between it (this area is called a caulk joint). Check these areas carefully once a year and make sure there are no holes, cracks or other signs of deterioration in the caulk. If you find any damage, you can either repair the caulk yourself (we recommend using polyurethane caulk) or hire a handyman to tackle the job.
Plants like moss and ivy can invade the mortar between your bricks/stones and weaken the wall. Carefully remove ivy or moss tendrils that might have snuck their way into any small cracks in the mortar.
Unless advised by a professional or using products specifically for use this material, don't paint or use waterproof sealants on your brick/stone. Applying a sealant or paint will trap moisture in the building and may make it difficult to detect areas of deterioration in the future.