[Richard and Rhonda]

Mine is in the passenger side bay with the outdoor faucet. It is concealed behind a panel.

Here is how to find it.

Park the coach. Don't run any compressors. Flush operate some air device until the supply pressure is depleted. Turn on the red switch in the toilet. Go outside and listen, you should be able to hear it run.

One of the coach to coach differences is that on some coaches the 12v pump supplies pressure to the toilet and the air pocket door. On mine, it only supplies pressure to the toilet. It's on my list to replumb the air supply for the door to run off the 12V pump.