I tried to use LED taillights on my 2001 ford focus zx3 and when I put the LED bulbs in only my driver’s side worked then put old halogens back in and both sides worked again I even went and bought another set of LED thinking it was a bad LED still same problem any ideas thanks
Yep, don’t use LEDs
Yes, LED bulbs are not compatible with your vehicle .
Are you sure it had halogens? Incandescent has been the norm in those places for decades. LEDs, done right, are fine but many aftermarket LEDs are deficient in many respects and, as you are finding, trouble.
I checked the Carid website and I think the LED’s should work in your focus Try turning the LED bulb 180 in the socket and plug it in again. Could be the polarity was backwards. Or maybe you got a bad bulb. try switching the bulbs side to side as a test.
PS… Your focus does not have Halogen bulbs in the Taillight’s so maybe you have the wrong kit.
Good point about LED polarity: they work one way and if reversed do not.
I replaced the head light bulbs in my lawn mower with LED bulbs and no problem, but I might be mistaken but seems to me some bulbs needed resisters or something to make them work.