underhood fuse box

[1990LTD]

I can 'scan' mine to get you the power distribution diagrams if you like

That would be most awesome. I'm going to buy an EVTM for my car but that would still be great.

[1990LTD]

oh and I won't be doing this for a while, I'm not touching it until I have everything figured out beforehand

[1987cp]

oh and I won't be doing this for a while, I'm not touching it until I have everything figured out beforehand

Same here.

[91waggin]

Isn't it just as easy to select fuses that are consistent with the gauge of the feed wires? Or better still, choose fuses according to the specific fuse link they're replacing? Seems to me it'd be much more trouble to look everything up in a book, but maybe that's just me.

When you're choosing fuses according to the specific fuse link they're replacing, it helps to be able to make sure that the fuse links have not been replaced with the wrong thing in the past. Also, having the book lets you know what fuse links control what, which is great if/when a fuse blows and shit stops working, you know what fuse to check.

Mostly, I just like to have the book to tell me what I'm looking at so that I don't have to figure out what I'm messing with as I mess with it.

[1987cp]

Ah, when thinking of going by fuse link sizes, I was blindly assuming the links were original.

[91waggin]

You probably could get away without one while doing it, but it would probably be harder.

It's simple: information is power.

[85crownHPP]

i knew i was forgetting something...

[Mercracer]

Pete and I are using different fuses for the same accessories in some cases and both cars have not blown a single fuse to date that I know of so it seems there is some flexibility in choosing how to fuse your box up. In my install thread I show most of my fuse values as well as what those fuses are protecting. Be careful taking the panel apart and rewiring it..the little tabs that hold in the spade connectors like to break on you and then that slot in the fuse box is pretty worthless unless you come up with some way to secure it.

I recommend writing the entire fuse box circuit out on paper multiple times making sure that your wiring is correct. Looks as if you may have everything you need in that one fuse box as it has a lot of fuses an relays already in use. That gives you a bunch of flexibility when it comes tome to rewire it to your liking.

My advice is to not mess with 20 year old brittle plastic. It may be a better option to cut wires and move circuits than to roll the dice. The option I am using is adding a second small fuse/relay box and moving things to that as I need to. I found several in bone yards in various vehicles including the V6 FWD Lincolns.

[gadget73]

+1 on not monkeying with this unless you have an EVTM. If something goes wrong, you're going to want tbe be able to identify what circuit each wire feeds. I also use my EVTM very frequently. Its really handy having the original wiring diagrams in front of you. I've taken to photocopying pages and then hand-writing my modifications on them so I have a record of how it used to be as well as how it is now. I just leave the copy inside the book, paperclipped to the original page.

[85crownHPP]

I have a bunch of notes and diagrams scribbled down in a memo book that no one else would ever be able to interpret, lol

[85crownHPP]

oh yeah, have fun!

these are for a 91, but they should be mostly the same

[1990LTD]

So generally speaking I find out the size of the fusible link (with my awesome new EVTM), determine what size wire it is protecting, and then choose the best fuse for the job?


For the sake of argument, I have a 16ga black fusible link, meaning it was probably protecting a 12ga wire, correct? Then going by this chart I found

Wire Gauge Recommended
Maximum Fuse Size
00 awg 400 amps
0 awg 325 amps
1 awg 250 amps
2 awg 200 amps
4 awg 125 amps
6 awg 80 amps
8 awg 50 amps
10 awg 30 amps
12 awg 20 amps
14 awg 15 amps
16 awg 7.5 amps

I should probably stick a 15 or even 10 amp fuse on there since the max is 20 for a 12ga wire, formerly protected by the 16ga fusible link.

[1990LTD]

does anyone have a fuse box wiring diagram for a 95 town car? that's what my fuse box came out of, and i can't get the damn thing unclipped to see what fuses are powering what wires.

[1990LTD]

hm actually i could just use my multimeter

[Mercracer]

So generally speaking I find out the size of the fusible link (with my awesome new EVTM), determine what size wire it is protecting, and then choose the best fuse for the job?


For the sake of argument, I have a 16ga black fusible link, meaning it was probably protecting a 12ga wire, correct? Then going by this chart I found.

Fusible links are 4 wire sizes smaller according to every reference I have ever seen. If you think about it, 1 wire size does not make any sense.