I haven't found any noticeable impact of cabin A/C on the frunk temperature. I'm confident the heater doesn't reach there either but you will get some heat from all the electronic components under and around the frunk and it certainly is heated by the sun (your color may vary). Until someone tests is, I'm assuming it is a little warmer than ambient when it is cold or cool out and about the same as ambient when it's hot, unless the truck is sitting still in the sun.