Replace 12v Battery Fuse

[Larry Trout]

2010 RX 450h. My 12v battery is not holding a charge. I have a new 12v battery I purchased from Lexus ready to install but wanted to check the battery fuse before I finish installing. How does one do that? I see the red box that attaches to the positive terminal, but didn't want to risk breaking it while attempting to locate the fuse. Any thoughts you may have regarding not holding a charge (beyond just a bad battery) would be appreciated. If the fuse is bad, can I get one from any place other than a Lexus dealership as the closest one is a couple of hours away.

I'm also getting the dreaded "Check Hybrid System" message and am waiting for the new hybrid battery to be installed, but I wanted to troubleshoot things before they come out in a couple of weeks. The only code I'm receiving is P0A80, indicating the need to replace the hybrid battery, which was replaced at 230k miles only 6 months ago by Green Bean Battery. I'm hoping it's truly just a hybrid battery issue and not the whole hybrid system at fault. Granted, the car now has 260k miles on it but I hoped to have it around a bit longer.