They are usually located low and inside the heated part of the RV. Look under cabinets and closets. Look near the water tank and try to see where the pipe is headed. Also common to locate the pump under a bunk. If your water pump is controlled by more than one switch they often use a small circuit board to control multiple switches. The switch(es) could be good but if the circuit board is bad -- no power to the pump.
Bob & Donna
'98 Gulf Stream Sun Voyager DP being pushed by a '00 Beetle TDI