The computer connected to the LED isn't responding...otherwise you would get 1 blink that means NO codes.

You need to have someone with dedicated MB scanner have a go..

That computer in is the box under hood & should be marked CARB.

__________________
MERCEDES Benz Master Guild Technician (6 TIMES)
ASE Master Technician
Mercedes Benz Star Technician (2 times)
44 years foreign automotive repair
27 Years M.B. Shop foreman (dealer)
MB technical information Specialist (15 years)
190E 2.3 16V ITS SCCA race car (sold)
1986 190E 2.3 16V 2.5 (sold)
Retired Moderator