I have a friend that called me yesterday and said his tahoe wouldn't start. He ran up he street and came home to take a shower and get ready for work. When he went to leave to go to work he got in it and turned the key to the on position not running and forgot something in the house got back out and went back in the house to get something. When he came back out a minute or two later turned the key back off and tryed to start it and nothing just cranked. When he called he said the security light was flashing with the key in the on position. I figured he had the passlock on. So I told him to leave the key in the on position for 10 minutes and then try to start it. He tryed that and said the security light is not on know but still just cranks. I am going to take my trailer over there tonight to look and see if I can get it started otherwise tow it to my house. Any ideas what to try.