location of horn CLK 55 AMG
The low tone one is located directly behind right-hand (viewed from driver's seat) headlamp assembly: black plastic and silver metal, stamped with Mercedes star and PN 005 542 1220.
The high tone one is directly behind grille, slight to the left (viewed from driver's seat) of the star, and in front of radiator: all black plastic, PN 005 542 1320.
My low horn wouldn't sound, so put a 12-v source directly to both horns: high horn sounded, low one dead. Based on prior experience with horn failures, it is probably repairable by opening up and simply cleaning the electrical contact points, but it is RTVd together so not worth the time, so buying a new one, $87.



