Ensure that there is water in the fresh water holding tank. Lack of water could have burned out the pump.
Ensure that there is electricity going throughout the trailer, either from 120 volt household current or from the RV's battery. Open the fuse panel and check the fuses using a multimeter. Check the fuse located at the battery connector. Replace if necessary.
Turn the by-pass valve to the "off" position.
Flip the pump switch to the "on" position, listen for the pump rumbling sound and open a faucet to determine water flow.
Check the water supply line to the pump for leaks or obstructions. If leaks are found, replace the supply line. If obstructions are found, blow them out with compressed air.
Replace water pump according to manufacturer's instructions, if necessary.
