Having electrical problems..need some help please.
 

For a few months I've been having some electrical problems I have a 98 blazer when I shut off my truck it's fine then after hours of sitting when I go to start it up its dead and when I get It to start the air bag sensor stays on my dome light only works when I turn the switch on. I have had the battery tested it came back ok, I've had the alternator tested to it came back ok. So I thought I would take the fuses out and then the truck couldn't die and the truck still died. I'm not sure what's going on I'm not leaving anything on I've checked.