one COLD night, several years back, the fire dept called.. they had a Chrysler that the only way you could open it was jack open the door..no frame-bare glass it was +5 with a -20 chill factor..BUT, the car was running, and the heater was on and nice and toasty.. I thought 2 SECONDS and said.. NAA.. dont want to chance the glass with that temp difference, which is why the FD called ME.. I referred it to someone with access to chrysler key codes..
--Shiva--