I have a really nice 600 SL 1993 and it suffers from the dreaded engine bay cracked wire syndrom which has made the car go into limp home mode the ASR light on the dash is on, a merc man came with a diagnostic machine and told me my ASR unit was nackered.................... my question is I also have a working 600 SEL 1992 does anyone know if the ASR unit is compatable so I can change them over and where is the ASR unit?