This topic is for a EXV2 model built in 2023.
We would like to power a permanently mounted 12v accessory and use the open fuse location #17, which has both terminals present. What are the current draw limitations that would factor in or are there any other considerations?
The power limitation comes from the DC/DC converter which has a peak amp rating of 30 amps and a continues amp rating of 25 amps. It varies on of the vehicle is equipped but yes typically, there is some extra power available. If I had to put a number to it, I would say about 10 amps. If equipped with air conditioning not so much. In your case you don't have air conditioning and F17 is not being used. F17 is fully wired to a plug in the cab. Plug is located at the front of the center console. Find wires going to center console and near it is a two-pin white connector. In your case should not be plugged into anything. Wire colors will be blue and black. Its mating connector would be Molex 50-84-1020 (our# U5830A-N) and terminals Molex 02-08-2004 (our# U5842A-N).
If F17 will not work the Bussmann 12v fuse panel located under front hood does have room to expand. In order to do so terminal Aptiv 12129409 (our part# U8281A-N) would be crimped on your added wire with wire seal Aptiv 15324980 (our part# U8241A-N) and fuse to match wire size would be inserted.
Fuse locations F11 through F20 are powered only when ignition key is on. Blue colored wires.
Fuse locations F1 through F10 are powered all the time. Orange colored wires.
Note: Chassis is not 12v grounded. Ground from your added accessory always needs to run back to DC/DC converter. 12V is isolated from the 72V battery pack so do not ground to the 72-volt side. Not all but most all small black wires within the harness are 12v ground.