Be very carefull jumping power to the fan motors. If the motors are stuck or shorted, there will be soo much current draw as to possible overheat the wireing. The Aux fan on my 87 325e would blow the fuse occasionally (15 Amp)due to I found it was drawing 15 amps because of worn-out bearings. (too much). I could have put in a larger fuse, but the wireing would not stand that and I didn't want my baby having a melt-down. Jumping power is only a trouble-shooting technique, and should NOT be a permanet fix. It just tells you where you're gonna spend your money!