Routing Power - 08/09/2022

For something so seemingly simple, powering this sound system gave me way more heartburn that I would have ever guessed.

The biggest issue was the BMW Positive Battery connection or the BST (Battery Safety Terminal), The BMW BST has quite the parlor trick. In the event of a serious accident, the BST has an built in explosive charge that will literally blow / sever the starter + engine bay power from the battery. Because it is explosive, it's not something I cared to mess with. Unfortunately it completely dominates the positive battery terminal with basically zero tap options for aftermarket devices. At least nothing that would support the types of loads I want to add. 
So I was faced with a dilemma. Cut the main battery lead after the BST and run the two ends through a distribution block that I can tap off of, delete the BST and install a regular battery terminal, or find a pass-through battery terminal. I favored the latter because theoretically it wouldn't require any modifications to the factory battery lead or BST.  After much searching, I found such a beast: 

What you're looking at is a Bassik Positive Battery Terminal made by KnuKonceptz with the addition of a configurable pass-through battery terminal.

While I can't say it was a joy to install due to how tight things are around the battery in the e39, I will say I believe it is a very nice option to consider as it doesn't require any modifications to the BST or battery lead.

With the battery tap problem sorted, and the target identified in my test fit stage, I was free the move forward with the actual routing of the amplifier power leads + fusing + quick disconnects: