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If you are referring to the battery disconnect relay switch, it is located near the entry door or on the overhead by the door or on the dash. If you didn't touch it, I would start by having the batteries load tested to be sure they didn't fail and are still viable. Most places that sell them can do this for you. Be sure and take a photo of the cables so you get them back the same way as it is easy to get this wrong. Dirty battery cables can cause this as well. Be sure to clean those and don't forget the ground lead to the chassis. Please get back to me if you need more here as all follow ups are included and fully expected.
Just checking back to see if you were able to resolve this issue or do you still need some additional input from me here? I will make a phone option available for you in case you prefer that method of communication with me.