DIY Wiring Harness

[mr giggity]

Alright, I'm in the early stages of planning my swap and have a general idea of what I want.

1999 Jimmy 4x4 with 4.3 will be getting a 5.3 from an 02-04 truck

the 5.3 would come with complete wiring harness and computer
i would reuse my 4l60e with flexplate spacer
the 5.3 would need its oil pan modified in order to clear my front diff

my only concern as of now is the wiring harness, being a cheap stubborn guy with electrical skills i plan on doing it myself

my understanding is that i need to connect all the 5.3l's loose connectors with the loose connectors on my body harness (pic):



I would be splicing connectors 11 and 14 into the leftover connectors on the engine which from my knowledge on the 5.3 consist of C100 (C105, C101?).

Am I getting this right?

[NITROUS]

It's hard to tell without wiring schematics what you need to do. You'll need to eliminate pretty much everything from the 99 harness except for the fuel pump relay, ignition, tach, oil pressure gauge, VSS, A/C controls and ALDL connector, etc.... I pulled my old style vortec harness out of the truck from the C100 and removed all of the wires I didn't need. You need to get a wiring schematic of the Jimmy and the 02-04 PCM so you'll know what to connect. I used weather pack connectors that plugged into the LS1 harness and made everything plug and play. I haven't done a 99 Jimmy so I'm not sure of all the details you need except for the schematics to get you going.

Good luck!

[ma.racing]

what he sead

[mr giggity]

the harness seems relatively simple

after looking at schematics for the Jimmy and 5.3 harnesses that mostly it's a color coordinated match, I also noticed that GM likes to leave their circuit numbers the same which is a big help

So far I know that the wiring connectors that are "loose" on the 5.3 are C100, C152, and C2 from the underhood fuse block

from here im just matching the functions with my "loose" connectors in the engine bay from the Jimmy which are C101, C104, C2 from fuse block, and C4 from my original VCM

I have matched all the C100 and most of the C152 connectors from the 5.3 with my Jimmy harness

I'll post an AutoCad layout of my progress soon

[ma.racing]

this is not on the point but glen quwagmier is the f**kin bomb ha ha

[mr giggity]

giggity giggity giggity to you


Progress so far...
I still have a few loose wired ends, such as the Axel Switch and the 2 Low References, any ideas? (and i'm not too worried about the fuse block)

[ma.racing]

qwagmier truth or dare ... truth ... do you have aids..... ha ha come on now were all just tryin to have a good time hear ha ha ah