I just recently purchased an 08 TL and am the fourth owner. One of the previous owners set the HFL passcode and I don't have it. Is there a way to reset it without going to the dealership? I have called them and they want $120 to do this. I did a search for this and found a thread that suggested touching the positive and negative battery cables for 20 minutes to reset the system. Is that all there is to it?