Under-hood KEYED Power

[ronemca]

Hey! I don't need an instant answer, but I do need a certain answer (please)...

I'm feeding the controller for a WMI system which I am installing under the hood, and I am looking for a source of on-with-the-key power under the hood.

I've looked at video's that say you can trap a feeder wire alongside pin #1 on any of the relays in the PDB/BJB, but this would not be my first choice.

And I have used fuse taps before, and yes - I can insert a fuse tap into any of 25 different micro fuse sockets - but they all seem to be ALWAYS ON...and therefore of no use to me.

I have two 20A J-case fuses for convertible top (mine's a hard top) but I can't figure out how to tap into one of those safely.

I will be introducing a dedicated inline fuse to protect the WMI controller.

So - where's the ideal spot for keyed power? :hail:

Sponsored

 

[ronemca]

Found.

 

[MX5Racer]

Found.

Are you keeping it a secret?
Might help another poor soul in the future who needs the info!

 

[Chef jpd]

Do tell!!!

 

[Nagare]

Are you keeping it a secret?
Might help another poor soul in the future who needs the info!

Agree! Doing stuff like that is the worst you can do on a forum. If I decide to go a bit rice and throw on some underbody lights to match my footwell lights, it'd be nice to know where to plug it in.

 

[ronemca]

Fair enough. I delayed adding details because there was some uncertainty about the specific assignments of the fuses in question. I came across a PDB diagram here: http://www.fordservicecontent.com/F...-Owners-Manual-version-1_om_EN-US_07_2015.pdf that clearly stated it was for 2016 N/A S550. But a friend who looked it up in the FoMoCo computer told me my diagram was slightly misleading (incomplete?)

Fuses 38, 40, 42 & 44 (2 x 20A and 2 x 15A) are labeled "Vehicle Power" in the chart I found. But the chart he got lists an incredibly-complicated collection of components that are on those four circuits. So I'm [now] somewhat leery about tapping into one of them to power my WM system.

However...

I installed a relay to feed the WM system straight from the battery...so that reduces the load (demand/risk) to the PDB circuit to microscopic.

Also...

The gauge of wire that the WM kit uses for their harness is no larger than 18 - and may even be 20 - so it's obviously not drawing very much current.

These two caveats ease my concern immensely.

Anyway - those four fuses are the only ones that are energized with the ACC *and* strike me as safe to tap. So I tapped #38.

BUT...

I also inserted a dedicated 10A Micro fuse for the WM system, so if it even tries to press its luck...it'll blow that fuse without killing anything else.

Sponsored