Make sure you do not have a tripped breaker or blown fuse servicing the water system. Check that your other 12v lights or appliances are working properly. 

Using a multi meter or 12V test light, with the pump switch on, check for 12v power at the pump. Inspect the wiring terminals that are feeding the pump to ensure their integrity.

If voltage isn't available there, check it at the pump switch. If you do not have 12V available there, the wiring from your power center to the switch is suspect.

http://www.easternmarineoutlet.com/RV-Water-System-Pumps/

Another thing to check for is water trapped within the system. If the system pressure cannot be lowered by opening a water valve, the pump will not activate. It needs a drop in pressure to fire the low pressure switch, and turn the pump on.

Recently a poster had a similar situation, and found a bad check valve that maintained the system pressure in one line from the pump.

If you have voltage to the pump, and cannot start it by opening a water line and bleeding some pressure, the pump's pressure switch can be bad.

If you remove the water supply to the pump, and turn it on, it should run if it's functional. Do not run it for any length of time, only a second or so. You can damage many pumps by running them dry.

  It is an aqua tec, are water pumps usually interchangable, as in different brands similar hook ups

Yes. They are similar using common inlet and outlet attachments, and usually two wire feeds, one hot and a ground.

If they are accessable, it's a fairly simple process to change them out. In some LQs they are buried and difficult to work on.