i have a 2000 blazer it keeps blowing the ecm 1 fuse. any ideas?

 

I don't know if you could get your hands on a gm tech manual sometimes the dudes down at the dealership are cool and will let you have a look, you need find the wiring diagrams for that electrical component. that being said once that's done get the voltage and resistance values for fuse and test with voltmeter. The diagram should give you the perameters that should be met by the circuit. once you get your readings from voltmeter trace back on diagram. that should hopefuuly give you some direction in which to go.