Today, one of my built-in Kidde smoke alarms started chirping every minute or so. Quickly figured out that the battery must be dying, but on this model, you can’t get into the battery compartment unless you unhook the unit from the AC wire harness. The Kidde site seems to be designed solely to sell these units to contractors; I couldn’t find any instructions on how to unhook the handy-dandy quick-connect plastic unit. Finally, after wasting 30 minutes on Google, I decided to look at it again. Standing on a stool and reaching up as far as I could, I was just able to reach the connector; I finally figured out that you need to squeze the “ears” to get the unit to disconnect. Things were easy after that; swap in a new 9 volt battery, reconnect the AC, and twist the unit back onto the bracket. But you know… a bit of instruction SOMEWHERE on the Kidde site would have been very helpful.