zcgame

I have a 2013 NV3500 HD passenger van, but I found my rear ac seems doesn't work. when I turned on the rear ac, the floor vent behind driver seat had wind came out, but vent on the roof didn't work. no wind came out from those roof vents, does anyone know what happened?

does anyone know which 2 wires are for the backup lights? and which one is positive? i want to hook up a backup sonar to the light...