Hello Group,
The cruise control in my 79 300SD works very intermittantly. On another webpage I downloaded the instructions on how to test the various componants. I tested the ohms on the servo, it was fine. I can't find the speed sensor! According to my repair manual it should be right under the dash, connected in line of the speedo cable. I have followed the cable from the speedo head to where it passes thru the floor and it isn't there. This is a very early 79 (12/78). When it isn't working it won't do anything. Sometimes you hit the switch and off it goes, and when it works it works perfectly. Next trick is to re solder all the board connections in the control box. Anyone have a clue to what componant is most likely the culprit? Even when not working, when you hit the engage lever you hear a slight click under the dash..Big thing that is annoying me is I can't find the sensor! Thanks for your help! John Winn