The type and size of the resister in each circuit on bulbs 'certified' CANBUS can be the problem. You need to systematically go from bulb to bulb swapping back to a 'filament' bulb until you find the one that is causing the error. This might take days. You have to leave it in long enough to be absolutely sure the bulb you swapped out is not the one you are having trouble with. Only through a systematic troubleshooting approach, can you find the bulb (or bulbs) that are causing this problem. I will also point out that since these bulbs are usually bought in sets, you may have to 'swap' out sets of bulbs until you find the 'set' causing this error. It takes a systematic approach, and time. If you are easily confused and forget where you left off or have done, write it all down as you go along. Remember, you have to take the time to insure the problem is isolated, or you'll be wasting your time hunting and hunting where the trouble is.