Had a head scratcher today with the HWH system

[Rustymayes]

It has been since Thanksgiving that we were out with the coach. We had a trip planned but the wife had foot surgery and we thought better of going anywhere until she is further along with recovery. I had been putting off doing the annual inspection and service so today I thought I would at least fire up the coach and run all of the systems to exercise everything. I fired up the engine and generator and ran the HVAC and Furnace and the water systems, all was fine. I went outside and noticed that the coach had not lifted to ride height so I went in to cycle the air dump and found the HWH system would not react at all. The blue and green LEDs were lit but no pump actuation or level lights were lit. I cycled the salesman switch and still nada. I unplugged the main plug on the pump unit its self and plugged it back in and then checked all of the fuses and still nada. I placed a cal into HWH but just got put back on their call back list. I cycled the salesman switch a couple of more times and the system all of a sudden decided to work. The FWS and the jack system work just fine now. My question is, what is going on when the system fails like that? Why does cycling the salesman switch fix it? I am pretty sure that the key was on the accessory position for several days and possibly weeks so the system was powered up. I guess for the same reason the Wifi at the house has to be cycled now and then as with many electronic devices like our I phones. I would love to understand why and why this can not be engineered out or in to these systems. Anyone have real insight and knowledge about this? It is troubling because there seems to be no rhyme or reason to it so one never really knows if just cycling the system will fix it.
The good news is that everything in the coach works just fine now and I found no signs of rodent intrusion anywhere.

 

[Jim]

Following . . .

 

[Neal]

Why does cycling the salesman switch fix it?

I can't speak to your specific scenario but the reason the salesman switch typically corrects things is it removes 12V power from various controllers allowing them to reboot. It doesn't remove 12V power from everything, there are 12V systems that are powered at all times regardless. Slide controllers for example may need this from time to time.

Our coaches typically have power on non stop. Most computer "things" don't do well with power on for years and sometimes need a reset.

 

[J&JD]

am pretty sure that the key was on the accessory position for several days and possibly weeks so

Why would you leave the key on “accessory” for long periods??

 

[Rustymayes]

Why would you leave the key on “accessory” for long periods??

CRAFT'S Disease! It was not intentional.

 

[Rustymayes]

I can't speak to your specific scenario but the reason the salesman switch typically corrects things is it removes 12V power from various controllers allowing them to reboot. It doesn't remove 12V power from everything, there are 12V systems that are powered at all times regardless. Slide controllers for example may need this from time to time.

Our coaches typically have power on non stop. Most computer "things" don't do well with power on for years and sometimes need a reset.

My question is why the genius minds that build these systems have not come up with computer or control systems that reboot themselves and just self-correct or design out what ever confuses the system in the first place. It seems like such a fundamental thing to find a solution to.

 

[Rich W.]

That’s worse than CRS. At least you don’t have to worry about burning up the points!