just realize my back doors are not locking or opening using the key fob. anyone ever had this issue?

 

I had this same problem with my front doors, sometimes they would lock after you started up and when you stopped and pulled the door handle to the first detente the rear doors would unlock and not the front. I had to use the key FOB to unlock them. I was also have other electric gremlins with my X the back up sensor would come on as soon as you put the car in R with nothing in back of me. Or with something in back of my the wouldn't come on at all. Finally last October the battery went. The car was dead as a door nail. I had a new battery put in. Guess what all the gremlins are gone the doors work fine and so do the back up sensors. So I would look at how many volts you have with the engine off it should be around 12V and when running, it should be 13.5V or better. If the volts are the low on either I would look at the battery as the culprit.