The headlights and running light are out.
When vehicle headlights go out, normally a simple fuse or light bulb replacement can correct this issue. However there is a known problem where the headlamp assemblies, sockets and wiring are melting due to high heat and resistance in this wiring. GMC has issued a number of technical service bulletins, as well as campaigns recognizing that there is an issue with the lighting system on the GMC Acadia. Campaigns are repairs that can be done free of charge to the customer. I would recommend scheduling an appointment with your dealership so this problem can be corrected as soon as possible.
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