1988 Ford Bronco II Main Cab Harness Diagram

[Herms88BII]

Since my BII is down and it is too cold to work on it outside, i decided to yank the electrical system out of it & create wiring diagrams for all the harnesses and during this process fix the wiring issues im experiencing.

The first one i have completed is the Main Cab Harness (including the portion in the engine bay). I dont have all the connectors named but would be willing to update the drawing based off of anyones input.

I've gained alot of mechanical knowledge from this forum and since i'm an electrical engineer by trade, i figured this could be my gift back to the community.

Stay tuned for more (wont happen too fast, maybe another week or two and i'll have the engine harness mapped)

- Aaron

[SmokeEater829]

Holy crap balls! You are the man. I pulled the dash out of my 89 B2 today to work on a few things. This will definitely help me trace a few wires!!!

THANKS FOR THIS INFO!

[Herms88BII]

No worries dude! Here's another document i created to go along with it...its still a work in progress (havent verified all the wire gauges) but its a nice companion to the schematic.

[jhammel85]

Looks like a TON of work. Someone should really put this in our library...Well done man!

[jhammel85]

By the way...I've had issues with finding out what #5 and 8 are myself. No idea where they go..They've always been unhooked.

Will you be updating us on what goes where?

Thanks alot for this! It's a great diagram..

[Herms88BII]

The plan is that as I get a more complete view of the electrical system (chase circuits from one harness through another) i'll go back and update each print so it is complete.

Once this is done, i'm going to redesign the cab & engine harnesses to relocate the entire power distribution system (using a Cooper Bussmann RTMR for a power distribution module) and EEC to where the cubby & glove box are currently...This should get all the relays/etc (but not the fuse links) out of the engine bay and raise the electrical system to a higher/safer position in the cab. I'm also going to be using an environmentally sealed 102 pin bulkhead connector to pass wires through the firewall (will allow for easy engine swap in the future) & am moving the passthrough to the passenger side.

Its probably going to be about 200+ hours of work to do the whole thing but its what i do for living (sometimes) and something i enjoy so it shouldnt be too painful.

In the end i hope to provide prints for how to do the rework i am doing that are accurate and easy to do. Our trucks are old...they need all the help they can get!

[Psychopete]

That is awesome.

[Mark_88]

Wow...when I opened the first document I thought..."oh, great, a mess of wires..."...then I blew up the image and started tracing the wires...awesome!

The second document was what I was thinking of when I was looking at the first...what are the connectors and what do they look like...

This will earn you rep points all over the place...I will start that out...and thanks for taking the time...