Knowing that the brake booster pump have a life of its own, it's probably a good idea to disconnect its fuse before doing any brake maintenance. Sure, you could simply disconnect the battery but, then you lose radio settings. So, which fuse or relay should I disconnect?
Disconnecting the 12V only loses the clock & (I think) calendar settings. Radio presets remain on my '17 Prime and my wife's '17 Prius.
