I had a Code 2 on mine, i.e. control module. Maybe you just need to check the connection to the airbag in the steering wheel? Steering wheel has to come off for that. If you do that, then you should inspect and at least clean the contact rings. Just a guess on my part - others will know far more about it I'm sure.

__________________
Len
'59 220S Cabriolet-SOLD and living happily in Malta
'83 240D 351,500 miles original owner-SOLD
'88 560SL 41,000 miles - totaled and parted out
https://sites.google.com/site/mercedesstuff/home
'99 E300 turbo 227,500 miles
'03 SLK320 40,000 miles - gave to my daughter
'14 Smart electric coupe 28,500 miles
'14 Smart electric cabriolet 28,500 miles
'15 Smart electric coupe 28,000 miles