Fuse Box Question 2019 Tacoma TRD

Looking to use an Add a Fuse to the interior fuse box, does anyone know which side of the fuse blocks are the hot side? The inside or outside of the fuse connection.
Don't have a test light handy at the moment.
And guessing it would be the same on both sides of the fuse block?

Thanks

 

I believe power outlet is only on when the truck is on

 

Got that, but which side is the hot side of the fuse connection for each fuse, one needs to know that to properly use the Add a Fuse.

 

It has been a while since I took out my add-a-fuse but I think the inside edge was the hot side. Made sense so hot was right in between the two rows of fuses. If I recall correctly, I had the wire end of the AAF pointing towards the inside edge. So If you leave out the "original" fuse in the tap and the new circuit still works, the AAF is in the correct orientation. If the "original" is removed and the new circuit doesn't work, it is backwards.

 

The slot in the bottom left is always powered. I have my constant power add a fuse tapped into there.

 

The one with the "hash" line through the rectangle?

 

Yes, also I did not know it mattered when using an add a fuse. Maybe I just got lucky but I’m running three of them into my fuse panel and just plugged them in with zero issues. Two for the dash cam and one for the ECT always on relay.

 

It does seem to matter. I noticed my other fuse tap wouldn't work unless I oriented it the opposite way.

 

If the AAF is backwards, everything "works", but the two circuits are in series. If one fuse blows, both will go out. If the AAF is correct, the two circuits are in parallel and will work no matter what happens to the other.

 

Okay that makes sense, I guess neither of the things I use them for are critical or use high amps. I used the lowest amp fuses I could find that were switch power so I guess this is not a problem for me but good information for the future.

 

What does the 7.5A fuse labeled USB go to? I have a 22 limited and it is blank. The label says USB, but has an X and no fuse rating, as if it is intentionally left blank. It does have keyed power though.

 

Powers the usb port either on the center accessory panel below the radio (right next to the cigarette lighter) or its in your centre console.

Left side of the fuse box is the supply (meaning its the "hot" side). Left side of the add-a-fuse should supply both circuits. Though, Ymmv - left and right are subjective and sometimes the "right" way to plug in a fuse creates more problems than it solves.

 

looks like earlier model years had P/Outlet No.2 in that spot, and it went to a cig lighter in the center console. At some point the label changed from ‘P/Outlet No.2’ to ‘USB’, when USB outlets were added in the center console. Second half of 2020, the label on the fuse box changed again, and now says ‘USB’, but it is marked as empty (lined through). It is a keyed hot, and I use it with an add-a-fuse to run a separate usb outlet.

What I’m wondering is where the other end of the original circuit goes to now. Does it just end at a connector that isn’t plugged in somewhere under the center console, does it even go anywhere. I’d rather tap it than use an add-a-fuse.
Hope someone knows.

 

Damn, thats smart and simple.

 

I’ve seen people post issues after they ran an add-a-fuse, oriented backward, to run lights off their INJ fuse. It’s a really bad idea.

 

This video is a good explanation:
https://youtu.be/YNc0FfeL6rw

A good video on a good way to hunt in your fusebox:
https://youtu.be/K2iKXj82354

 

https://youtu.be/2xMHKCFwx7Q?t=1403

I plugged mine so the cable is towards the center of the fuse box. I did what this guy did and it hasn't had any issues.

 

Fuse List for both the under hood and cab fuse boxes: