Buick Repair Questions? Ask a Mechanic for Answers ASAP
Check the door switches in the door jamb. Sometimes the driver side gets beat up by the seat belt and closing it in the door. If the switch is beat up it's usually the problem. If it is, then replacement should resolve the problem. In the mean time you may be able to remove it and disconnect it to get the light out.
Please let me know what more I can do to assist you today. Also, please remember to rate my answer, Just Answer does not compensate me for my time and resources. Follow up questions are included in the price of your question. If you are using the free trial, or have a subscription a rating is still required.Thank you so much!
I am sending you a short youtube video. This may not be the same as what you have on yours, but should give you an idea of the switch and where to look.