Honda's documentation for the Clarity says that preconditioning does not function when plugged in to a level 1 EVSE. We have a level 2 where we live in the winter, so I wasn't that concerned about it, but I decided to try it out here in our summer locale where we only have the provided level 1 unit. Sure enough, try to precondition over hondalink and you get a pop up saying you cannot. However - if you use the app to stop charging, preconditioning becomes available again, and the app shows the car as charging again when you activate it. In my test, the charge did still decline a little while preconditioning, but it does appear that it is drawing power - at least through the info on the app and the indicator light on the car (don't have a kill a watt, etc to check.) So for those of you on Level 1 looking to warm up your car this winter, you can - just tell it to stop charging first.