Cost of AC repair or replacement on 1998 clk 320

The entire AC unit is probably not nec to replace as you more than likely have some component failure and not a total system failure unless the entire AC unit has been contaminated by foreign susbstances. I would check all fuses first. If everything looks good check functions of the AC unit. If you have no air blowing from the vents you probably have a failed blower motor. If you have air but it is not cold you may have an AC leak. Definatley don't get rid of it without being looked at by a professional.