BSD/RCTA diagnostics and recalibration

[TNForester]

Hello - I'm new here. I had a VERY minor fender bender a little while ago on the passenger rear bumper, and immediately after the BSD/RCTA has been deactivated. Visually, there is nothing that appears to be physically wrong with the sensor or the mount under the bumper. Granted, I have not yet taken off the bumper. Dealer very quickly wanted to replace both ("They have to be replaced in pairs or it doesn't work") and charge $1500. Now, I'm not a technician, so I can't say that it won't ultimately come to that, but it seems like there might be a couple things to do between now and then. 

Can places like autozone run code checks to see if there is a treatable problem with the radar system? I'm wondering if it could be something as simple as needing calibration after a disruption from the bump. If not an auto parts store, any other recommendations on more affordable ways to chase this down? Thanks in advance.