I replaced my transistor and harness a week ago...as soon as I left the dealer with the transistor i pulled over and put in the new one it stared working.. it was freezing that night..thing is i didnt have the screws with me to mount it..I let it hang on the carpet the metal end and placed a towel around it so it wouldnt move (stupid)..a few minutes later again no heat. Does anyone know if the hanging on the carpet caused transistor to fail again so soon? I looked to see if carpet was melted were the transistor rested..nothing just indention from the metal. Fan comes on for about 2 sec. when i turn key.. like it did before i replaced the transistor.

 

Was it mounted on a heatsink? If so maybe it overheated & died.

 

Not sure what a heatsink is..I'm talkin about the transistor under the dash connected to the blower motor..I just let it hang touching the carpet without putting the two screws back in.