2017 questions

Well, I am now the owner of my third Tundra, but this was almost a 15year jump past my old Tundra. It has a lot more buttons. .
First, my BSM monitor was working but then stopped. Most of the info I can find online says to clean them, try disconnecting the battery, or disconnect and reconnect them. I am assuming I have to get inside the bumper and hit it with some water - is that correct? Is there anyway to determine which one might be bad?

2nd. This tundra has 140K miles. I have to entire car fax but didn't see anywhere where the water pump was replaced. My last tundra went over 200K before the water pump started acting up. So, I am wondering if I should go ahead and get it replaced, or if I can take my time with this. I am thinking the serpentine belt probably needs a change too, but, again, my last tundra's serpentine belt looked great when I did the timing belt change at +200k miles.

thanks