2016 Sierra- FOG LIGHT NIGHTMARE!

[KeithO2]

My truck had passenger fog light out. I ORDERED NEW OEM. However,  got light and noticed connector was corroded. The connector thats in front of bumper. So i cut the 3 wires and used heat shrink butt connectors. 2 black and one brown. I matched them exactly like connector. Took one off at a time. 

Fog lights wont turn on!

Relay clucks, button work and illuminates fog lamps on dash. I took DV meter and have power to splice on both sides and have power to fog light plugs. 

I took new light and plugged it in. STILL WONT TURN ON!

Yet I can hook new light up to 12v atv batter and it illuminates. I mean WTF IS GOING ON. Shouldnt be this complicated.  Please help!

 

Picture below is what I cut and spliced exactky same way. 

Passenger side was originally out and drivers side lit. I never touched drivers side. Now both out. 

 

Please note: fuse is good, relay is good, switch works, power all the way to fog lights. These are stock cat eyestyle oem fog lights. 

[AlabamaChevy]

Ok, Based on what I found online the brown wire is your wire for the fog light control and the blacks are your grounds.  I would check your ground wire the black one's going back and make sure they are not corroded. I have not found where they ground at. 

 

2016-2018 Silverado/Sierra - Wiring Systems And Power Management - Component Connector End Views | Pdf Download (cardiagn.com)