1975 Grand Prix Cruise Control troubleshooting

[Horse]

I recently bought a 1975 Grand Prix, the previous owner said that the cruise control had worked. Upon investigation, I discovered that the vaccuum supply hose was missing, I installed a vaccuum hose and picked a plugged port on the carburetor and attached it. I do have vaccuum when engine revved, servo functions. I have power at one of the wires going into module but no power on other wire when pushing the button on turn switch)(I am pretty sure the other wire, black,comes from the switch). Any help would be greatly appreciated! I am not a mechanic but I have some basic skills. Thank you.

 

[SnowDrift]

Is the diaphragm still functional? Follow the hoses and I think there is a cable going into what I'm calling the diaphragm.

 

[Horse]

Yes, diaphragm works. I think they call this the servo. I can make the diaphragm work by bypassing tha cruise control module. I need to troubleshoot the module, how it is activated. I know that you need to be traveling 30+ mph to activate it, I was told that there is a magnet inside the module. The power to the module is the first thing I would like to eliminate as a problem. Thanks for the reply SnowDrift!

 

[Scottydoggs]

its been so long since ive been under the hood of these 70's cars. i cant even remember how it all worked. its a crap set up i know that much.

id make sure the plugs to it are getting power when the switch is thrown, may be a pita to do if you need to be going 30 mpg to test it.

and yes, they wont turn on till your going that fast, maybe 35 mph.

 

[SnowDrift]

Respectfully, there is probably a better forum out there for the older G body cars. This forum is strong on W-body, though. I've got an '81 Brougham that I bought when I was in high school with the 350 olds diesel in it. I think I found a forum for that era a while back, but can't recall what it was. Yours is the same platform as mine. Post back if you find a good one, though. I'd like to re-visit that.