Where is the load levels censor switch in a 1999 cadillac sedan deville?

There isn't a "load level sensor switch" in the traditional sense in a 1999 Cadillac DeVille. The DeVille uses a system of load-leveling sensors (not switches) within the rear air suspension struts (or shocks, depending on the option package). These sensors don't have a separate switch; they're integral parts of the air suspension system itself.

If you're having issues with the suspension, the problem likely lies within one or more of the following:

* Air suspension struts/shocks: These are the most common point of failure. They contain the sensor and the air spring.

* Air compressor: This pumps air into the suspension system.

* Air lines and valves: Leaks in the air lines can cause problems.

* Ride control module (computer): This controls the entire air suspension system.

Instead of looking for a switch, you should diagnose the problem by checking for air leaks, testing the compressor, and potentially checking the ride control module's fault codes using a scan tool. A qualified mechanic specializing in air suspension systems will have the tools and knowledge to diagnose and repair the issue.