Tail lights, running lights & dash lights not coming on

[MIABARBI3]

So to start things off I have a '05 Nissan Altima. My ex installed a radio in my car (as well as a system that is no longer in my car). That was well over 2 1/2 years go & in the past 4 months my passenger headlight went out, then my passenger brake light (both which I replaced & work just fine), but then my (both) yellow running lights, (both) tail lights (for night), and dash lights (like ac/heater control lights...not speedo) went out. My headlights, brake lights & turn signals all work just fine. I have gone to Advanced Auto, Pepboys & AutoZone to see if possibly it might be the fuses, but they all say it's an electrical problem. If anyone has exerience with this type of problem or had the same problem themselves with a solution, I would REALLY appriciate any help I can get. Nissan dealership is the LAST place I want to take my car due to any solution to a problem will not be cheap.

[DJ_B_Easy]

When you say that the system is no longer in the car, does this mean the head unit was removed as well? If the head unit is in the car, and the amps/speakers have been removed, how long after that happened did the issue turn up?

It sounds to me like a loom somewhere was cut or damaged and took out everything within it. Seems that everything effected would only be functional with the parking lights or headlights on. Most aftermarket head units have a dimming feature that requires a tap into that system so that it knows when the headlights are on. If your ex didnt know what he was doing, he might have bypassed the OEM tap (not 100% sure if your car has this or not) and went elsewhere.