2008 wont change in 4 wheel

I have had this problem since I purchased my 2004 used (owned for 7 years). Try putting it in reverse and backing up. I find this works 99.9% of the time. Discovered it because I back into my drive way (which is uphill). This also works when the lights are out all together. I also had a problem with windows going down (unexplained). Can't remember exactly, but had do with one of the cylinders or or valve cover/gasket. I don't have this problem since I had a it repaired. I think anytime there is a problem that might even slightly interfere with the electrical system, things go haywire. Hope this helps.