Christian, What Dave said is true about the circuit breakers. The circuit breakers click on and off just like a relay and make a louder noise., but they are not supposed to unless there is a problem. The the Coolant fan relay will also make a quiter click as it turnes on and off, but if the contacts are burn't or bad the fans won't come on or may come on intermitally. Since you know the fans are good, the otterstst is good, then make sure all the contacts are pushed in good , replace the CB with a 40A. Then the only thing left assuming the wiring is ok would be the coolant fan relay. You can see some of the up graded replacements on my web site. If you have any questions, you can call my cell # at 972-672-3739. John Hervey http://www.specialtauto.com/modifications/shtml