The answer to 'sprinkler system thin grass' is that a malfunctioning sprinkler system is a common cause of thin, patchy grass. Symptoms include uneven water coverage, dry spots, and stunted grass growth. Potential solutions include adjusting sprinkler heads, fixing leaks, and improving the sprinkler system's programming and coverage.
If the issue persists or you're unsure of the cause, it's best to call in a professional landscaping or sprinkler repair service. They can diagnose the problem, make necessary repairs, and ensure your sprinkler system is operating efficiently to keep your lawn healthy and green.