You might try triggering the coil of a second relay off of where you have the led hooked up now. Then you could turn on the led through the contact of the second relay. You will have to find a relay that will trip from the 6 or 12 volts but not trip on the voltage generated by the fan. I guess you could spin the fan and measure the voltage and current generated by the fan. Just waht I would try. I do however try a lot of crap that doesn't work.
Neil
