I have a 1998 s70 glt and yesterday I shut the car off and the engine blower didn't turn off. It didn't sound like the normal engine fan that stays on when then engine is running hot. I didn't think anything of it at the time but when I came back the battery was completely dead. So I had to get a new battery and when I put it in the fan immediately started going again. I do not know what is wrong and would appreciate any help.

 

Bad fan relay, likely.

Talk to the guy in the other thread whose fan won't come on... Maybe your fan and his can work something out so that they both work half the time.