85 f250 help

i got an 85 f250 diesel 4x4 the cruise does not work any help

What have you checked so far? Fuse good? Current to servo? Switches working properly? Ground wires good? Help us a little more.

i got an 85 f250 diesel 4x4 the cruise does not work any help
check to see if both brake lights are working

check to see if both brake lights are working Huh? Is this going to be like "Is your refridgerator running?"
My C.C. is the on the blink too (87'/302) so I'm also interested. Are you going to say an incomplete brake curcuit(a lite out) will cause the C.C. not to engage?

That is a good suggestion. The brake switch is wired to the cruise to shut it off when brakes are applied. If the switch or wiring is bad, the cruise will not come on. Check the connector to the switch also. These are a known fault area.