The journey continues with the purchase of the new 4 element bulbs for the truck. Got the new set of lights installed. One fog light bulb DOA. Contacted seller and got a new one on the way. Bulb arrived yesterday, plugged it in DOA. Contacted seller again, two new ones on the way this time. High failure rate must be acceptable to quality control.

Bummer. They never lit up or lit up then quickly died?

Make sure you check the "bad" bulb in another base (that is if they have bases) if it lights up the base is possibly bad. (archaic lighting knowledge from before LED's...)

Never lit up. I tested the socket with old school bulb and a 2 element LED and both worked.

Just a thought.

LED's are a Light Emitting Diode. Diodes only conduct in one direction. LED's only conduct with proper polarity applied.

Take one of the DOA ones and reverse polarity and see if it works. China quality control being what it is, they may have the terminal connections within the LED reversed.

Long shot but what do you have to loose? Now if it works you still have a problem because I'd never suggest reversing polarity on the vehicle.

More of a science experiment.

Seems like a lot of work for some lumens.

Plugs on the LED's are directional and only go one way. But that does not mean they were not wired backwards. I will give it a test later today.