The battery in my wife's car, '14 Murano SL died on her last Saturday, luckily at home. It tried to start but clearly the battery didn't have it anymore to start. So, I bought a new battery since this was the original battery and figured it was time, installed it, easy, no problem. Hopped in it to start it up, crank but no start. Checked what I could think of but no luck. Looked on this forum for others with this issue, no luck. I have had battery failure twice over the years on her '09 Murano and had zero issues after those changes. I decided to check fuel pressure since I saw some on here had the same type starting issue, no mention of it after a battery change though. That process in the manual states to remove the fuel pump fuse and start the engine to relieve the pressure on the fuel line so it can be separated to install a pressure gauge. I pulled the fuse, pushed the start button, the engine cranked and tried to start . I was curious so I reinstalled the fuel pump fuse and the car started up. I have had no further issue, it starts and runs great.
I put all this here to ask if someone can explain what really happened. I realize the low battery could have caused some strange things to happen, but obviously power was removed when I removed the battery, so what needed to be "reset" in the fuel pump circuit to make it happy and start?
Just collecting more information for the "next time".