Leaking Bathroom sink drain connection to Gray Tank

TwonuCampers

I have discovered a leak beneath my Tab 400. I have isolated the leak and occurs when draining the bathroom sink. No water inside the Tab, only below when water drains.  I have removed the sink from the wall, no water or leak.  I am assuming its at the connection to the gray tank. The question to the forum is, how do I access the bathroom sink drain connection to the gray tank.  I see where the shower drain connects, but how do I access the sink drain connection? 

qhumberd

Depending on your model year, several folks have removed or modified the folding sink, so using that term you can search for those. My mod of the 2019 round folding sink involved removing the sink to expose the drain system and shows the drain above the floor

https://tab-rv.vanillacommunity.com/discussion/15361/t-b-400-bathroom-folding-sink-removal-add-panels-and-shelf#latest

There is a connection behind the outside shower box that transitions the corrugated to pvc just above the grey tank. Have the pull the shower box to reach that area, which may be where water could get to outside 

Good luck 

qhumberd

The bottom of this thread has those pic’s behind the outside shower and below the bathroom 

https://tab-rv.vanillacommunity.com/discussion/16114/quick-disconnect-for-the-outdoor-shower-a-success#latest

TwonuCampers

@qhumberd, thank you for the reply to my post. First, excellent cabinetry work! Looks like a great mod to the bathroom. Secondly, I appreciate you sharing the links to your pictures, I did not think about looking through the outdoor shower box to get more visibility to the sink plumbing. Going to pickup an endoscope from Amazon and probe underneath the shower pan and through the outdoor shower box to find where the drain connects to the grey tank. Happy Camping this season.