Hmmm, some thoughts on my coach and it's differences. Cannot verify "mini fuse" have not checked for it since just read this thread, will check.
I can operate my smartbeds using either auxiliary or main pump as they work either way. I only use switches in HWH and Services bay, since the hokey switches on the side of the coach have not worked in years. That may be the reason this works this way on my coach.
After the accident, and all the hassle of that, it was determined that a pin on the plug into the main Silverleaf computer on the dash was bent, and that caused the TM102 error we kept having. S/L fixed that for me, and not issues since.
To remind everyone the HWH Control Board needs around 100A-DC current for several milliseconds to start an operation, i.e., leveling, extending the jacks, putting out the slides, etc. The batteries cannot seem to provide that amount for that period. Always have shore power, the main diesel running (this would preclude leveling since the compressor wants to pump up the system) or the genset running to provide that power so you don't burn a diode on the motherboard from lack of that voltage and current requirements. At least this is what I remember from the discussion on this forum about 18 months ago. I follow that procedure and have no issues with the HWH system.
Thank you for the information and the drawings, have added it to my library of stuff I keep for the coach.
Monty & Janet - 2007 Alpine APEX 40 MDTS
S/N - 75715 - Retired - Master Certified RV Tech