| Q: I have an easy question, for the past couple years my 2012 XC90 randomly has rear lights out, but they are not burned out or broken. Most of the time, I can just slam my hand on the outside of the light fixture and the bulb will just come back on. Does this mean I need a new wiring harness for the rear lights? or is it something else?Thank you!!! A: it looks like just bulbs loose contact, you may want to grease all the bulbs, there is electrical grease, I don’t think you need any harness, it could be due to moisture, |