So I have no taillight, brake light or backup light on the left rear. However, the turn signal works. The bulbs are good and I replaced the socket thinking that was the issue. No joy. Can anybody point me in the right direction?
Did you by chance use Leds instead of filament bulbs? Leds in the rear need to be SRCK polarity because the position on the positive and negative contacts is rotated 90* compared to normal 3157 bulb type. (Sold over a million $ worth of Leds since 2010) 😇