Where is the Cruise Control Sensor on '85 190E? Is it attached to the back of the speedo head. Is there a way to test? My cruise control sometimes works fine other times it will fluctuate speed when engaged. I have checked solder joints on cruise control computer and heated them up again with soldering iron to make sure none were bad but to no avail. I have also read that it is possible for brake light bulbs to cause this problem. How would you check the above??? Any help or link to website would be greatly appreciated.
Thanks in advance,