Cruise control in a 1984

[04_6.0]

Does anyone know of a good guide to trouble shooting the cruise in a 1984 f-350. Mine doesnt work and idk if i even have all the parts there for it to work. I have the servo, cable, and the buttons on the steering wheel but what else it there. There has to be a brain or something right? And through my searching there is something on the t-case or something? Ive checked all my vacum lines and coffee can thing for leaks.

 

[nyteshades]

I can't remember if the 84 is the same as the 88 or not, but on the 88 there are 2 boxs under the dash for the cruise control and a speed sensor on the end of the speedo cable (tcase end) in addition to the parts you listed.

 

[OLDBULL8]

I've got the whole trouble shooting for an 89, the 84 should be close to that. Check the grounding brush under the horn button on the turn signal cam. I don't have time right now to copy and send the wiring dia. will do it later tonite.

 

[gandalf]

Also, there should be a relay in the mix somewhere. On my '86 the cruise and the horn quit at the same time. I replaced a relay under the dash, about mid way across, and they both came alive again. I'd guess that the '84 was built about the same way.

 

[nyteshades]

I think the cruise uses the horn relay instead of having it's own separate relay

 

[04_6.0]

my horn works and the fuses are all good. now a relay idk? I dont have any kind of wires comming off my speedometer cable at all??? and inside of the horn/cruise buttons there is a ground and a blue and yellow wires is that right?

 

[nyteshades]

The speed sensor in the tail of the tcase should look like this.

http://www.rockauto.com/catalog/raframecatalog.php?carcode=1124323&parttype=3988&a=FRc1124323k385941

There's a picture next to the price.

 

[Silver Burner]

There is also a switch attached right above the brake pedal arm that needs to be depressed in order for the cruise to work. When I changed my master cylinder and booster I discovered this because all of a sudden my cruise quit. It's just on a flimsy plastic deal, so it easily can be moved to not be depressed when the brake is not being used. Check that first!

 

[04_6.0]

Ok nyteshades I found the one for my truck up under the actual servo. There is a small adapter thing that has two wires that come off of it and then goes into the servo harness then inside of the cab. Ill check on the switch for the brake pedal. is there one on the clutch pedal also?

 

[Silver Burner]

Don't know about the clutch, I'd have to check. Never even thought about it when I was messin with the brake one..

 

[towtruckdave]

Does the speedo work?

 

[nyteshades]

The clutch switch must be closed for the cruise to work. Prolly easiest way to check is to try and start the truck without the clutch pushed in.

 

[04_6.0]

yeah the speedo works fine it has a little jump from 0-10 but after that its smooth. umm i believe the previous owner bypassed the clutch switch because i can start it without pushing the clutch pedal in. i found the plug in it has a piece of wire bridged across the plug feet. So i need to take it out and try that?

silver burner: i have the switch that has the vacuum line comming off of it. and there is another one that has a two wire hook up.

 

[nyteshades]

yeah the speedo works fine it has a little jump from 0-10 but after that its smooth. umm i believe the previous owner bypassed the clutch switch because i can start it without pushing the clutch pedal in. i found the plug in it has a piece of wire bridged across the plug feet. So i need to take it out and try that?

I would

 

[Garbage_Mechan]

I think that the clutch switch has 4 wires, 2 for start and 2 for cruise. May need to jumper the other 2 if they are there.