jakeb

iTrader: (9)

I am thinking about using the entire fusebox from the donor z28 I bought for my swap. Does anyone have a wiring diagram for the fuse box for a 99 fbody. Or even an entire chassis diagram would be nice.

I was going to slim the harness down but if I have everything why buy more relays and fuses when I already have it. If I can hook everything up at the fuse box and c220 and c230 it will work just as well.

bczee

iTrader: (12)

i have rewired one of the fuse boxes from a 2002 Z28.. (is the same for 99). It is not hard to figure it out. I just brought some new connectors.. It is not a factory Manual Diagram.. but it well give you an Idea of what you can do with it.

attached is a diagrame that I drew up of what I did.. the fuses, relay and stuff.. are in the same location on the fuse box.. I combined what I needed from the two boxes into one box.

jakeb

iTrader: (9)

thanks, that helps a lot! Never thought about combining into one fuse box. that is a good idea.

Andy1

bczee,

Thanks for posting that fuse box info. I have a question: I notice theres a Battery Ign 12+ 50A fused line going to Battery Ign Relay that goes to PCM Ign 15A blue 20 & 57. Is there a reason you used the 50A fused source and only power a 15A fused circuit? Seems like way more than needed (or perhaps it's simply because it was already there for you to use in the Fbody fuse box?).

Andy1

bczee

iTrader: (12)

Andy1... hope I can explain it correctly as I understood it.

The Battery power come into the box and you have to supply two types of battery 12volt.. Battery Direct and Ign controlled circuits. But you know that..

Now to your question..
"I notice theres a Battery Ign 12+ 50A fused line going to Battery Ign Relay that goes to PCM Ign 15A blue 20 & 57. Is there a reason you used the 50A fused source and only power a 15A fused circuit?"

The 50amp fuse powers the "Battery IGN Relay".. That relay powers all of the IGN required circuits.. coil #1 and #2, Injectors, Transmission and the PCM (20 and 57). So.. it will be possible that that relay will be pulling more than the noted 15amp of one circuit, and that you see as over kill.. If it was maybe only one 15 amp circuit.. the 50amp one could be left out and connected directly to the Battery. But since the relay must power at least 5+ 15amp circuits.. I left/used the relay connected to a 50amp fuse else it would be direct battery anyway. Would not think it would harm anything that way.. but it would be protected up too 50amps..

But as you last stated. ..:
"Seems like way more than needed (or perhaps it's simply because it was already there for you to use in the Fbody fuse box?)."

yes. GM pretty much had it there to use and as I traced the circuits in the boxes, I just mod'd the box to meet my circuit needs into the one box. Yes.. I may have over did the design or engineer of this box. But it was a lesson in wiring and in the end, it is better to be safe.. (I guess.)..

If there is a problem that you see. Let me know.

BC

jakeb

iTrader: (9)

I have a few questions too....

In the fuse block diagram at the top with thethree fuses, IGN coil #1, IGN coil #2, and injectors...there are connections going from the PCM then to coil bank 1,2, and injectors on the left. From looking at the other diagrams I have I assume the power should come IGN relay and go direct to those groups, ign 1,2, and injectors?

Also in the third row of fuses you have PCM Ign 15a then going to blue 20 and 57 at the PCM. Those are then being powered by the IGN relay. In the engine diagram I have it shows pin 20 and 57 having orange wires to it and HOT at all times? Which is right?

Then PCM pin 19 should be hot in start/run...that should be coming from IGN relay?

Is the drawing off a little bit or am I thinking about this wrong?

thanks for the help!!

bczee

iTrader: (12)

Jakeb

Thanks for catching that.. the Drawing is incorrect. but the worksheet of assignement is correct.

My bad on putting the Blue 20/57 and Blue 19 in the incorrect boxes.. I will correct and update the attachements later..

jakeb

iTrader: (9)

ok good deal
I did notice that everything on the worksheet looked correct.

The 50amp fuse at Battery IGN makes more sense now too as well for Andy1 as you have multiple circuits coming off that. IGN 1,2, injectors, and PCM pin 19