1987 Cruise Control Issues

Ok we have ditched the old vacuum servo and have pulled parts from a 2004 expedition that has a 6 pin connector. We decided to go with an all electric servo. Any idea what else we need besides the servo. did not know if there is another box we will need. the vehicle is available for us to pull what ever parts we need. also cant find any info on wiring this system up. Does anyone have any diagrams or idea how to wire this system so we can make cruise work. We are planning a route 66 trip next year and cruise would come in handy!! Any and all help would be appreciated especially any wiring diagrams of 2004 expedition and a parts list!!
 
We are planning a route 66 trip next year and cruise would come in handy!! Any and all help would be appreciated especially any wiring diagrams of 2004 expedition and a parts list!!
With the roads as crowded as they are and the percentage of the WORST drivers ever, I truly doubt you will be using your cruise much......
3 years ago I drove from central Florida to Eugene OR. to pick up and tow back the mustang project I have.... The traffic was so bad that I gave up on my " toyhauler/Harley trailer to see America in my retirement..... Its just not worth the battle, " In my Opinion"
Of course I am the last generation to be raised without social media and got to see this country before it went to SH!T.....
 
Now I am looking at going a new direction. I have been told that the six wire type cruise control off of a 2003 Expedition would work. It has a single 6 wire plug and was told that this doesn't have a connection to the ECU. This is a cruise that has the servo and module all in one. But here is the question. I have been looking all over the internet for a pinout of that 6-wire plug and can't find one anywhere. Does anyone know where these wires go!! I am attaching a pic of the pigtail. Hope someone out there knows where these wires go! Thanks in advance to any help that you can provide.
 

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If that's specific to a 2003 expedition, you might need to grab your hands on a 2003 expedition ford wiring diagram manual.


Missing the top cover, but cheapest one on Ebay
 
Thank you for showing me this. From looking at the print this cruise wont work either. I am completely at a loss as to why the other cruise wont work. All the outputs are right! We have moved the amplifier and servo to another vehicle that has the same parts and found them to work also. I realize I am missing something but as to what I have no idea. Even had other people come behind me and check all my connections and outputs. I really dont know what to do other than drop the money on an after market cruise and be done!! Any suggestions??
 
I wouldn't give up yet.

Check one more thing. On the Mustang, the way that the cruise system is disengaged if by way of a vacuum dump valve on the brake pedal. Press the pedal and the servo loses vacuum and canot control anything. Release, and a valve closes and allows the servo to fill with vacuum. Do you have this setup properly?

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Here's what the dump valve looks like on the mustang pedal assembly. When the pedal is returned to rest position (brake pedal released, foot off pedal), the brake pedal arm pushes the plunger on the valve and closes it, allowing the cruise servo to build vacuum and function.

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I thought that when you pushed down on the brake pedal it opened the valve and dumped the vacuum i.e. the valve is spring return so fail closed? You adjust the valve towards the firewall such that when the brake pedal is resting the plunger is just off the back of the pedal arm.
 
I thought that when you pushed down on the brake pedal it opened the valve and dumped the vacuum i.e. the valve is spring return so fail closed? You adjust the valve towards the firewall such that when the brake pedal is resting the plunger is just off the back of the pedal arm.


That is how it works. I think my phrasing was a bit confusing so I edited it.
 
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I was scratching my head after I typed that and I have it wrong. With the pedal assembly upside down it threw me off. Found a video on YouTube on the brake light switch and had a clear image of the vacuum dump valve which got me squared up.

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Found a post by @General karthief that has a really good tech info on this in Post #4 of this thread: