I recently sought out a way to be able to charge things while my car is parked. I own a 2013 Chevy Cruze and the power outlets are normally off when the key is off. This overrides that behavior by removing a relay and replacing it with an always on connection. DISCLAIMER: This overrides something in the electrical system in your car. If you’re not comfortable making these kinds of modifications, then don’t. If you do decide to try, then do be careful and please don’t blame me if something goes wrong.
I had found this post regarding it, but could not load the images, so I took the information I have and created this page with my own images of making both the power outlets always on instead of the switched by the key. The first step is to locate the fuse box just inside the driver’s side door on the dash. Open the door by pulling on it, it will reveal the fuses:
Next, squeeze the two side clips of the fuse box to hinge it outward.
Remove the right-most relay (nearest the steering column) labeled R3 on this chart, and fashion something to connect the two large paddle connections. I pulled out the fuse box for photographic purposes, but it could probably be done without fully removing it, but just hinging it down and removing the relay.
Fashion something to connect the two large paddle connectors. In my case, I found an old plumbing part and cut it down with the Wiss M3 sheet metal cutters that I have on 99-year lease from my Grandpa and will pass along to my son/grandson at some point.
At this point, it’s just a matter of putting things back together.
Just put the cover back on and charge away all day and night. You can save that relay and undo the change at any time. Remember not to drain your car battery too much…you have been warned.