I have a 1999 Fleetwood Bounder on a Freightliner chassis with a Cat Engine. There is a warning buzzer that starts up intermittently and when I press on the brake it stops but when I release the brake it starts again.
Sometimes it just stops on its own after 30-120 min of buzzing while driving down the road. All the gauges read good and the air pressure is excellent to the brakes.
Since you say all of your gauges are reading normal and that there is no warning light associated with the warning buzzer, I would only be guessing to tell you what the problem is.
One thing you can check is to make sure that all of your leveling jacks are fully retracted; if they are not that could be causing the problem you are describing. Low hydraulic fluid in the leveling jack system can also cause this problem.
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