I have a 2000 F150 that I put LED headlight. bulbs into. Supposedly, they are CANbus ready. Apparently I am one of the small percent that had an issue. My bulbs never changed from bright to dim. The bright indicator would illuminate on the dash but the bulbs never changed. I didn't know if my brights were the ones on, or the dims. Also, I had occasional flickering out of the blue. I got these decoders and plugged them in between the bulb and harness. Everything is perfectly fine now. No more sudden flickering and my brights and dims do what they are supposed to. Very much recommend these decoders. 5 stars.