I installed Sony CDX 250U in dodge durango SLT 2000 with 4.7L. But now instrument cluster lamps and dimmer switch not working. All the other external , internal lights and warning lights of the dashboard are working. None off the illumination light of the instrument cluster are not working. I check the fuses and they are all intact. How to bypass and test the dimmer switch?

 

Undo everything you have done to find where you went wrong.