Poorgie,

Check your headlight and brake light grounds. A bad headlight ground in my 745T caused the wipers to come on when I hit the light switch. A broken hatch hinge ground wire for my third brake light in my 245DL wagon caused the instrument lights to come on when I stepped on the brakes. You have some ground wires that are broken, loose or corroded. Clean, repair and tighten them and your spooky light problems will go away. I'm not sure if the 92 240's retained the same service light reset switch ... but on my 88 there is a lever reset switch on the back side of the speedometer. Drop the under dash driver side cardboard cover (removing the front retainers will do), reach up behind the speedo and flip the lever up and it will reset for another 5K miles, that is if it's the same reset as my 88)
Hope this helps.