Can't connect Garmin 510 Edge to Iphone...suggestions?

I can't get Garmin express to download onto my machine, but that doesn't really bother me. I just bought a Garmin 620 Forerunner and an Edge 510. I managed to get the 620 connected to my Iphone no problem. The 510 Edge on the other hand, just won't connect. My Iphone lists the Edge 510 in the Bluetooth connection window, and the Edge will sit there with the little circle arrow trying to connect, but they just won't pair up. Does anyone have any suggestions? It is an Iphone 5s. All software is up-to-date on the phone and on the Edge. The 620 now connects automatically whenever it is within range of my phone...I can't even get an initial connection from the 510. Since the phone 'see's the 510, I have to assume it is an issue on the 510 side of things.