Well i Just replaced my headlights with hyper whites and my turn signals with APC blue bulbs they are 3157 just like the stock bulbs and they are 12v like the stock ones but they both are not working doesnt make any since..........any suggestions?

 

u put em in backwards maybe...when i changed mine they didnt work at first either and the i turned them around and they started working

 

Check to see if the sockets are burned too. GM has a problem with that.