This is a follow up report.
We've had the brand new RV for just 10 days, but are already having a couple of issues:
1. The grey tank valve does not appear to close completely. When I tried to remove the sewage cap to connect the hose, I noticed the pipe was already full of waste water, while the grey valve was in close position. After I removed the cap, the water continued to flow at slow speed and never stopped. The water started to gush out once I pulled open the grey valve as expected. So apparently there is a leak. Later I tried to push close the valve tightly, and tested with faucet on, and water started to come out right away. I noticed two things: the valve handle does not appear to close in all the way (see picture below, the right one for grey), and, the valve is extremely hard to pull out or push in. I did push very hard and the valve stopped with a gap.
Is this a defective valve? For the new W floorplan, the grey and black tanks are located on the passenger side, and there is a long pipe across the entire body to connect the tanks to the outlet on the driver side, so the cables for the valves are much longer than other RVs that I have used. Could this be the reason for the mechanic issue? I plan to take it in for service.
2. The second issue is a bit scary but I'm not certain if this is real. It has happened three times - the engine won't start after I turned ignition. No cranking sound, just lights came on dash and then all went away except the engine symbol remained on. I had to pull out the key and tried again, and usually on the second or third try, the engine started. I doubt this is a low battery issue because engine didn't even crank. Has anyone had this problem or I was doing something wrong? This is the 2015 Mercedes chassis by the way.
Once this happened in the middle of no where, without cell coverage, I was frightened.
I appreciate your input!