It will start with the block heater plugged in, as long as the hood is fully closed. But if you open the hood without pressing the "run" button after using the remote start, the engine quits. Probably best not to let it run too long with the heater still plugged in though. I'm still learning the quirky little things about this wonderful vehicle.
ps. mpg's during this very cold winter in MN has been between 20 - 21 in mostly city driving, which I think is pretty good. That includes a lot of using the remote start, idling when going inside for a few minutes, etc. I never used to let my vehicle idle when going inside primarily because I couldn't lock the doors and keep the engine running. But now I can and with the extremely cold weather I like to keep the inside of the car warm when going inside for a few minutes. I'm guessing I'll see something more like the estimated combined EPA 24mpg when warmer weather and non-winter blend fuels come ....
2014 Grand Cherokee Summit EcoDiesel Cherry Red w/Jeep Brown interior
2011 John Deere 1023E diesel tractor
2009 Jetta TDI (better half's ride)
2007 Harley Softail Deluxe
1966 Beechcraft Bonanza "V-tail"
1930 Ford Model A - restoration in process