I have a 98 E300 DT. The air conditioner does not cool and I hear a hissing noise from behind the dash board. I know that there is a diagnostic that can be activated by holding down one of the buttons on the air conditioner control in the dash.

Do you know where I can information on how to activate the diagnostic and then evaluate the meaning of the codes?

Also, what is you opinion on the life expectancy of a rebuilt compressor?

Thanks