They never fail to fail ON and drain the battery to ZERO volts. Most chargers today won’t even attempt to charge a flat battery and the odds favor the battery being trash at that point anyway.
I don’t see a reason to have bilge pumps hard wired to the battery if all they can do is kill the battery and not pump anyway.
Ayuh,..... I run bilge pumps through a float switch,.....
Years ago, I bought a rule automatic bilge pump, that was 'puter controlled,.... turned out to be trash in my book,....
It would turn on every few minutes, if it "Sensed" water it pumped it out, but the time it spent "Sensing" ran the battery flat in a couple days,....
I hard wired it through a float switch instead,....
Years ago, Ted was in my area, 'n stopped by to visit me at my river house,....
After chatting for awhile, we were going to go for a boat ride in my ole tinbarge, but the batteries were flat dead, because of that automatic sensing bilge pump,.....
The next day, I rewired that pump, through a float switch,....