I had a bad ground somewhere all electronics inside are flicking on and off i used a cable to jump the negative battery cable to a ground and all power accessories came on perfect. Ground buses were just cleaned and looked good all new battery cables. New 140amp alternator. I know there is a main ground under the ICM is there any others I should be aware of? Need help as quickly as possible!

EDIT: meant to say i used a cable to connect negative terminal to the body and everthing came on