First let me say, I don’t know anything about vehicles except basic basic stuff. I inherited a 2009 GMC Sierra hd it has 110k miles. Brand new battery, I replaced the master 175 fuse from the positive cable.. Sometimes not starting, other times starts great but couple mins all the gauges flatline lol then they will come on or some will come on. Windows won’t roll down or back up, then they might start working again. Any ideas what is going on ? Bad connection or starter issues is it something simple ?

 

Any suggestions?