How does one test the ignition control unit on a 1991 420sel? I don't specifically have a problem with mine, as far as I can tell, but I'm curious. What symptoms would it cause? Is it easy to test function?

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Der Panzermann und Fraulein Fahrvergnuegen

1991 420SEL 201K "The Big Blue One"
1985 300DT 205K chassis/285K engine nee California emissions "Goldbug"
1983 300TDT 255K "The Womble"
1983 300 DT 214K "Sea Sprite"-Rear-ended a truck
1983 300SD 285K "The Donor" Gave his life so that others can live
1980 500SL Euro 105K "Der Panzer"

You could measure the voltages and scope the waveforms but around the shop if you plug it in, and it runs, then it's good.