The auxiliary fan is an electric fan mounted in front of the radiator and condenser. The auxiliary fan is turned on by temperature sensors when certain pressure thresholds are reached in the A/C system, and provides additional cooling to bring pressures down below these levels. If the auxiliary fan system fails (fan never comes on) it causes the operating pressures to remain high and adds extra heat and stress on the A/C compressor, which can lead to premature failure.
Fitment specifics:
2001-2005 C240 Base Sedan
2003-2005 C240 Base Wagon
2003-2005 C240 4Matic Sedan
2003-2005 C240 4matic Wagon
2001-2005 C320 Base Sedan
2002-2004 C320 Base Wagon
2003-2005 C320 Base Coupe
2003-2005 C320 4matic Sedan
2003-2004 C320 4matic Wagon
2002-2005 C230 Komp Coupe
2003-2005 C230 Komp Sedan
2002-2004 C32 AMG Sedan
2003-2006 CLK500 Base Coupe
2003-2006 CLK500 Base Conv
2004-2005 CLK320 Base Coupe
2004-2005 CLK320 Base Conv