Water Pump will not shut off

[nplenzick]

03 Safari Sahara, MH is winterized all water lines have been blown out. I was doing some work today in the couch ( shampooing the carpets). When I went out to check if the carpet was dry I notice the fresh water pump light was on in the kitchen. I figured I must have knocked it in the on position. Went to turn it off and it won't go out and the pump wouldn't shut off. I have three switch's for this pump, all three will not shut the pump off so I unplugged the pump. I suspect there's a bad relay somewhere but have no idea where it would be. The front driver side distribution panel has no relays that are marked for water pump. No relay found by the pump ether. Here's another weird thing, I found a fuse in my rear fuse panel marked bathroom that I pulled out, that killed the pump light in the bathroom and the switch in the hallway but not the one in the kitchen. Does anyone have any ideas where this relay could be or any other ideas what could cause this.

[Robi.1014]

On my 04-Dip, there is a latching relay module that provides power to the pump once you push the momentary-contact switch(s) inside the RV. But the "relay" is actually a sealed electronic module....so you can't troubleshoot the physical relay therein.

My observation matches yours: If the pump is pumping (as "told" to do so from the controlling module), the motor will run forever if the pump is without water (or has water but is sucking air for some reason). The electronic module will ignore your inputs at this point (it's laughing at us). In this scenario, water pressure cannot be achieved (no water to pump), thus the pump runs in a "no load" state ... which is also to say that it is not drawing very much current. Once the pump has water and creates pressure in the lines, then as the pump reaches that 30-pounds (or so) of pressure, you hear the pump laboring. It's at that moment that the pump's pressure-switch opens and current stops flowing to the motor. My observation is that the control module must "see" this lack of current flow before it "un-latches" and obeys your command (from inside the RV) to turn off the pump (the module, actually). The module then (and only then) turns-out the red-lamp at the momentary-contact switches (the "3" you mentioned). I know this sounds nuts (that's not the way a latching relay should work), but heck: that's what I've observed.

Above is how my module has worked from the git-go. Maybe others in the forum can tell you & me that we have bad modules. Location of this beast? Behind the panel in your water/waste bay. Monaco installers seem to have enjoyed mounting this unit so that it is quite difficult to get to.

[nplenzick]

Actually your explanation sounds logical to me. Here's what happened yesterday. As soon as I put the slide in the switches worked perfect. I operated the slide a few more times to try to get the switch's to malfunction and didn't happen. I found the latching relay which was next to the pump. Always thought that had something to do with the slide. The only thing that I can think of is ether the latching relay was stuck and the 12 volt surge from the slide unstuck it somehow or I have a pinch wire in that slide that has one switch. At least now I know where to look if it happens again.