Hello I’m at a loss on what to do for my 2012 3/4T suburban. The problem started 3 weeks ago where it just won’t start. It started intermittently then died. I cleaned wires and checked grounds then it was jumped. So clearly thought it was a battery. One new battery and it happened again. So we changed the starter. Nothing. Then my mechanic found a wire that looked frayed, changed it and it started. It worked well for 3 weeks. Then yesterday it happened again. I jiggled wires and it started. Now it won’t start again. Is it the wiring harness? I don’t know what it could be. Thanks.

 

Which wires running from what to where need jiggling ?

 

I wiggled the battery terminals and the wires coming off the starter. Didn’t work today, but yesterday it did. I’m taking it in, I’ve struggled with this too much over the last few weeks. I’ll post what the issue is. So maybe it will help someone in the future.