ernie1 wrote:
You didn't mention it but I assume you are having a problem with the gray water tank sensors and not the black. I take care of that problem by removing the drain plug and inserting my homemade wand which fits into the small drain plug hole and blasting away with a stream of water aimed at the sensor locations in the tank. Of course one should also take the time to clean the rest of the tank also. Works every time.
You are correct, I miss posted by calling the problem tank the holding tank when it is indeed the gray water tank that is causing my problem, sorry about the confusion.
I find no drain plug in the tank, only the main dump valve and it's a ways from the tank. It would be difficult to thread anything up into the tank. I might consider installing a plug in the bottom of the tank myself.