Trying to get cruise working again

[kas83]

I've searched, and found one thread about converting to cruise. My truck came with cruise control and an auto, and has since been converted to the ZF5 manual, and also a transfer case was added to the mix.

I seem to have everything for the cruise under the hood: servo with vacuum lines attached, throttle cable from servo attached to pump, all wiring connected to servo. On the inside, I'm not sure exactly what I have. The brake light switch is hooked up and operable, and has a splice for my brake controller. I don't have a clutch switch installed, but have a connector with a jumper, wires are both red with a blue tracer, hanging by the fuse panel. I have the auto steering column yet, steering wheel with all the buttons and what not.

If anyone needs any more info to help point me in the right direction, just let me know. I'll go over this thing with a fine tooth comb if needbe to get you answers. I don't have any manuals or wiring diagrams to go off of.

 

[david85]

I think this might help:

http://www.garagenet.biz/cruise.pdf

 

[Agnem]

What is your symptom?

 

[bike-maker]

I have a feeling I will be down this same path myself. Mine got the steering column out of a 89 during the ZF5 swap, which is supposedly plug and play. But so far, the accessory position on the ignition switch is inop, and if I try to honk the horn, it blows the fuse to the stereo. I have yet to be brave enough to push any of the cruise control buttons.
The manual swap shouldn't be an issue if the neutral safety switch (turned clutch switch in our case) has been bypassed. The vehicle speed reading comes off the speedo cable right next to the brake booster.

 

[kas83]

What is your symptom?

Cruise hasn't worked since the day I bought it. PO said that before the swap, everything worked fine. I'm trying to figure out what all I have, trace down any problems, and get it working.

 

[AZBLACKSMOKE]

I think this might help:

http://www.garagenet.biz/cruise.pdf

Cant get the link to work? Im hoping its a factory wiring diagram?

 

[david85]

Cant get the link to work? Im hoping its a factory wiring diagram?

Yes, thats what it is. Its the factory manual for 1985 automatic speed control in scanned PDF format.

Crud, I thought I was the only one that couldn't open the original link anymore. If anyone wants a direct copy, send me a PM and I can Email it directly since I have it saved to my hard drive.

 

[FordGuy100]

From what I know you can't have the clutch safety switch bypassed like that. With it connected it acts as though the clutch is being oushed in the whole time. So if it acts like the clutch is in cruise doesn't work.

 

[bike-maker]

From what I know you can't have the clutch safety switch bypassed like that. With it connected it acts as though the clutch is being oushed in the whole time. So if it acts like the clutch is in cruise doesn't work.

Crap, your right. So there's more jerry rigging to do to the cruise control wiring to make it work.

 

[OLDBULL8]

If you don't have HI Speed internet, it will take awhile to down load the PDF file. http://www.garagenet.biz/cruise.pdf You have to have this to trouble shoot the cruise control or you will just be chasing your tail.

The clutch switch is a magnetically operated switch, mounted on the clutch bracket. If you have it jumpered out the engine will overspeed if you have it in cruise and push the clutch in.

 

[87crewdually]

Try this:

Cruise Diagnostics

 

[bike-maker]

The first link worked for me.
On page 37-07-7, it shows the difference between manual and automatic setups. Automatic trucks (which mine and KAS83's would be) already have a jumper wire where the clutch switch would be on a manual. I don't see on any of the diagrams where the automatic's neutral safety switch comes into play. If that's the case, the work has already been done. Bypassing the clutch switch in a truck originally equipped with one however, would create a problem.
At least that's my interpretation....................

 

[FordGuy100]

I'm almost thinking about wiring it up with a LED on off switch somewhere. I can flip it on which will allow me to turn the motor over. And then going down the road flip it into the off position to use cruise control.

 

[kas83]

Ok, printed off the instructions in the 2nd link provided. Will get to testing everything in the morning and report back with my findings. Thanks for the insight so far.

 

[TLBREWER]

Check the vacuum release "switch" at the brake pedal. When the pedal is pushed in, vacuum releases and disables the cruise. Kind of a back-up to the electrical switch. Doesn't show up obviously on schematics. I chased wires for 2 days and finally found the vac switch in my truck not seated fully against the pedal bracket. Pushed it in and whalla, cruise worked like a champ.

Tom