I have an 1989 560SL.
When I try to use the cruise control sometimes - not often - it works okay for awhile. BUT...usually when I try to use it, it immedialtely accelerates (whether use it from set/accelerate or set/decelerate) and speeds up then slows down. It is so erratic that I can only leave it on for a few seconds before I touch the brake to turn it off - kind of scary.
Any thoughts on needed parts. Not sure if it is the amplifier or actuator of ???
Thanks!

I had similar experience with my cruise (86 300E) and it was the amp. The usual fix is to remove the amp and check/resolder connections.

Thanks for the info
Are these the connectors on the amp itself or ????

In the amp itself

where is the amp located?

where is theamp located?

Typically under the carpet and plastic covers of the front cabin area. A rectangular silver box with an orange cap on one side.

yeah, usually the amp , just re-solder, but you need a steady hand, also a comfy chair.... take your time....
good luck...