I had a bunch of battery corrosion so, among other things, I took the speed control servo off the right battery case to clean out the corrosion. When I put it back on, my speed control (cruse control) doesn't work. When I hit the switch to turn on the speed control on the steering wheel the the "cruse" lite comes on below the speedometer but the thing doesn't work. I checked the electrical and vacuum connections and all seem to be in place. I found it a little difficult to get the connector off the servo and ended up breaking the little green plastic pin that apparently insures that the connector stays in place but the connector seems to still go on properly. I have the factory service manual and on page 8H-3 it says to troubleshoot the speed control servo I should start the engine, disconnect the connector from the servo, turn the switch to engage the cruse control and check for voltage at pin #3 on the connector. I get no voltage at pin #3 with the brake pedal pressed or not depressed. Also when I pull the connector off the servo, the light on the dash does not go on indicating that the speed control is operating. (however, when I put it back on the servo the indicator lights)

 

check and see that you didnt unplug the vacuume hose at the pump (real easy to do) . hopefuly it will be that easy

 

Rebal: Thanks for the advise. I followed the vacuum hose all the way to the cowling and then all the way to the place where it connects to what I assume is the vacuum pump on the motor and all is connected.

 

Looks like I found the problem. I blew into the vacuum tube and there is a hole in the tube. must have bent it when removing it.

 

By chance did you check for codes when the problem started? I get intermitent failure of the cruise control and I get a 1595 DTC (speed control circuit A) which led me to think that it was an electrical failure....maybe that is incorrect? Maybe this means it could be a vacuum failure of some kind?