G Klasse Cruise Control Issue

Check the pedal switch and the fuse box. A blown fuse is often the cause. Also, inspect the throttle position sensor connections.

Where is the fuse box located on these older Gs? And is there a specific fuse for the cruise control, or should I check them all?

The fuse box location should be in the owner's manual. The cruise control fuse may not be clearly labeled, so check the manual. If those are fine, it's likely a more complex issue. Consider a workshop visit.

It was a corroded connector to the pedal switch, as the mechanic initially thought. 95€ later, it's fixed. I'm annoyed I didn't check it myself first!