In your Grand Design 5er, your "wet bay" or "Docking Station" as it's called for the Grand Design should have a spigot attachment with hot and cold faucets where you attach a coiled blue hose with a standard garden hose threaded connector on the other end.
I have found multiple ways to use this faucet for multiple purposes. If you have water in your fresh water tank, you can attach a garden hose to the end of the blue coiled hose, attach a garden sprayer squeeze handle, turn on the water pump inside your camper and you have water anywhere the hose will reach!
You can also use that same blue hose, attach a shorter standard garden hose and attach that to the black tank flusher. You can also attach a garden hose and put the garden hose under the camper and use for washing dishes and such outside on the opposite side of the camper or anywhere the hose will reach. Or use for washing the dog or muddy kids.
Here's a tip to make cleaning that tall front cap easier: Open the tail gate of your truck and back it up close to the 5er king pin, but not under it. Then use a short 4 or 6 foot step ladder set up in the bed of your truck. You can VERY easily reach the top of the front cap to wash it.
OK, you don't have water in the fresh water tank because it's in storage? No problem. Bring a container of water. Hook up the hose to the winterizing spigot in the wet bay. Flip the handle from fill or city water to "Winterize". Turn on your water pump, turn on the outside spigot for the blue coiled hose and you'll be able to pump as much water as you bring in your bucket.
Is the battery low or dead on your camper because it's been in storage? Plug in the trailer pig-tail to the truck, give it a few minutes to charge the battery a little. Keep it plugged in and the water pump will run. (try it, you've got nothing to loose, everything to gain.)
I do it this way because the front cap of my Montana High Country is actually a window and it gets bug covered. I had to come up with an easy way to wash it down anywhere, otherwise, it looks really ugly from inside the camper.
