Cruise Control Wiring help

[Kay86K5]

Hey everyone, wondering if there is someone who can help with this. I’m seeing if I can get cruise control working on my 8.1 swap in my 89 V3500. As you can see from the pics below, this was the original cruise plug that was in my truck going to the original TBI350. Flat connector with 5 wires going into it. I’m wondering if someone cam tell me what each wire does (which one is resume/accel, cruise on/off, etc.)? Tilden labeled the wires in the 8.1 harness, I just need to know which one of these wires do what so I know which one to splice to the 8.1 harness. Any help is appreciated as for some reason I cant seem to find anything on my internet searches.

Thanks!

 

[Kay86K5]

So after more research and talking it over with my brother...I'm pretty sure the plug in the picture above is what goes into the cruise servo that is off the intake (most of all these old TBI350 servo's had vacuum control with it too). Apparently there are wires that go into the cruise control module (which is supposedly under the dash on the column somewhere, haven't looked yet) that appear to be some of the correct wires that I need to splice into the 8.1 harness (cruise on/off, resume/excel, break, etc.). So my thoughts are to cut the wires going into the module and then splice directly into the 8.1 harness (then getting rid of the module and the rest of the wiring that went to the original TBI350 servo, since they are not needed whatsoever to run a DBW throttle body).

I may try this tonight or tomorrow...but in the meantime, anyone else tried to get a DBW LS to work with their original cruise switch in your square body? Kinda hard to find info on this on the interwebs, but some I found said it's possible doing it the way I just described...wondering if anyone else has had success too?

 

[dyeager535]

Link in my signature has the wiring diagrams. Don't think the cruise changed at all up to 1991 (and probably even later) after they quit using the speedometer cable driven setup somewhere around 1981.

Can't help with the DBW, but I'd think the "input" would still be the same regardless of the setup. You need all the same functions.

 

[Kay86K5]

Link in my signature has the wiring diagrams. Don't think the cruise changed at all up to 1991 (and probably even later) after they quit using the speedometer cable driven setup somewhere around 1981.

Can't help with the DBW, but I'd think the "input" would still be the same regardless of the setup. You need all the same functions.

Cool...I'll check out that link, thanks!

And I think you are right, the input/output should be the same, and Tilden was nice enough to pull out and label the couple cruise control wires in the 8.1 harness, I just need to find the correct matching wires in my trucks cruise control harness and splice correctly...I never thought it would be so difficult to find out which wire does what on these old cruise setups, haha