Help identifying these two things

[496bb]

Here’s a few more pics, both wires look to go into firewall. Can’t really see corresponding on engine side. I see absolutely nowhere for this plug to go.

Truck has all the trailering packages, possible it was for a factory brake controller? Truck had an old Kelsey Hayes hydraulic controller that I’ve removed, it had its own two wires running to the back and no plug that would

 

[Jgonick]

Finally found it- TCC They changed the colors in 87.... used to be brown & lt blue --

plugs into brake switch, or a special cruise control brake switch. Just be aware it is opposite than brake lights- meaning when you press the pedal it cuts current to the TCC -

 

[496bb]

Ok, so I’m guessing that maybe since 87 was first TBI year where they used a spacer for the qjet intake and maybe other one year changeover items- and I have a TH400, it’s not necessary (never has been plugged into anything)and can just keep dangling.

 

[Matt69olds]

The box is definitely cruise control, as is the mystery plug. The plug goes to the brake switch.

The cruise on these trucks is completely independent of the ecm/carb other than the VSS. So if you want cruise control, you need those components plugged in and functional.

 

[Craig Nedrow]

Yep. Purple and pink w/black stripe. I’ll try to get under there with a flashlight and see if I see any else that might help.

But if the other box is def cruise control only, I can remove it when I carb swap cause ECM won’t be controlling throttle anymore. (It’s a prefect spot to mount the new RedArc brake controller box)

I just bought a Redarc brake controller, and the rest for my 85, be here tomorrow. Hope to install it ASAP.

 

[496bb]

So if I’m swapping to carb, the cruise should still work- if it has VSS, and is there an easy workaround for that? Although, I can’t see where this plug can possibly go, two plugs already into the brake switch. Sorry, this is not my strong suit and just confused. The truck hasn’t really been running well since I purchased, so I can’t really say if the cruise currently functions or not.

 

[Jgonick]

So if I’m swapping to carb, the cruise should still work- if it has VSS, and is there an easy workaround for that? Although, I can’t see where this plug can possibly go, two plugs already into the brake switch. Sorry, this is not my strong suit and just confused. The truck hasn’t really been running well since I purchased, so I can’t really say if the cruise currently functions or not.

Not sure about TH400, but a 700r4- usually the cruise control is plugged into the brake switch ( 3 grey & brn wires) & the brake wires (orange and white). There was a vacuum brake switch that the vacuum line plugged into and the TCC wires -(brown & lt blue and on yours purple & pink/blk)