Issues with my civic ex 95 auto t

[Rodasgeo]

I have a auto 95 civic ex that I just bought. Had some overheating issues so I took it to the shop. Turned out to be the temp sensor so the mechanic replaced it said it was running fine. I go to pick it up and it turned out it won't start. When I turn my key to the on position the lights on the dashboard turn on and Im able to turn on the a/c, but when I turn it again for the ignition it doesn't click nor crank. The starter motor is fine because I hotwired the starter to the battery and it starts no problem. payed the guy and drove it home. Didn't want to leave it there because it seemed kinda shady. Car started fine until I took it there, but thats a whole different story. Could it be the battery thats just to old? Fuse or a relay? Please help. Thanks.