1.A graphite impeller within the vacuum pump fails causing vehicle faults. 2.Sometimes water ingress can cause problems with these pumps, often however the impeller on the spindle of the motor can break or shatter over time. 3.A broken impeller will cause a lack of air pressure / vacuum to be provided meaning actions of the pump will be inhibited. 4.It can also lead to a jammed motor which will lead to the pump blowing the 20A fuse and shutting off. fit motor part number:1397220291 And for pump part numbers 1397220291, A2308000648, A2308000548, A2308000448, A220800348, A2208000648, A2208000748, A2208000548, A2208000848, A2208001148, A2208001248, A2208000948. the roating direction of the Impeller wheel:contrarotate Suitable for the following models: For SL-Class (R230) 2001-2011 For 1st gen: 2001- 2006 - SL350, SL500, SL600, SL55AMG, SL65AMG For Facelift 1: 2006 - 2008 - SL350, SL500, SL550, SL600, SL55AMG, SL65AMG For Facelift 2: 2008 - 2012 - SL280, SL300, SL350, SL500, SL550, SL600, SL63AMG, SL65AMG For S-Class (W220) 1998-2005 For S280, S320CDI, S320CDI L, S350, S350 L, S400CDI, S430, S430 L, S500, S500L, For S500 4-, S600L, S55 , S55 L For -Class (C215) 1999-2006 For CL500, CL600, CL55AMG, CL63AMG, CL65AMG Colour:Black Material:carbon Package Contents: 1 * Graphite Impeller Wheel 8 * Graphite Replacement Fins Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.