SL500 R107 Passenger Foot well

[tristand]

I had a look at an SL, 1983, recently and when I looked at the passenger side foot well behind a panel I found a box about 5" X 5" X 1.5" with a cable running into it connected with a large plug.

Is this the cars ECU?

 

[tristand]

Picture of the box in question

 

[Ted]

That is exactly what the old ecus looked like.
Almost certainly analog rather than digital.

 

[BlackC55]

Yep. An ECU