This amount of current can only represent some interpretation of cold start enrichment. I had that happen on an 88 420SEL. Periodically it would just die for the customer. After driving for some time watching the EHA current it did it too me. and I saw the exhaust look like a diesel. Current ran up and down around 100ma.
I have to say I found the answer by accident but I guess it was concept driven. I inclose a picture of the connector behind the fuse box that includes the wire that goes to the starter from the KE controller. The green was evidently carrying enough potential from one of the other circuits to convince the controller that starting was taking place. I think anything but a ground potential will do this. The wire is normally grounded through the solenoid wiring when not starting the car. I was following this circuit when I took apart that connector. Cleaning it solved the problem.
Bosch Master, ASE Master, L1
33 years MB technician