@winter4w As I believe jokiin mentioned previously I would run the constant power wire directly to your battery (or another jumper location that attaches directly to the battery). This way you will bypass all of your vehicle electronics that may be at play. Your accessory wire should be okay with it's currently location. It has to be a constant power issue.
For testing purposes while you're parked use a long wire to run outside of your vehicle (through your rolled down side window) and under the hood to the battery. You'll either need to crimp the wires from your hardwiring kit to the extension wire or twist them together really well (and cover with electrical tape).