Installed my used JDM OEM taillights today in zero degrees. The problem I am having is the drivers side main bulb will not light. I changed the bulb. But the brake light does work so I know it is not the bulb. So what is it? Thanks.

 

In a single bulb system, the brake light and the tail light use separate filaments, even though both are enclosed in the same bulb. It may well be that the bulb is bad with one filament burnt out, or there could be some bad connection to that half of it—the bulb isn't seated in the socket properly, there's some corrosion or crud in the way, the connection to the socket isn't tight, etc. Try swapping bulbs with the other side to see if it's the bulb that's the problem or something else, and proceed from there as appropriate. (Also check to be sure that the bulb isn't installed backwards.)

 

Will try swapping the bulbs again to see if that is the problem hoping that it is not the wiring just strange that swap the bulb out once and it did not correct it.

Thanks