What would cause a Volvo S80 odometer to go black?

A black odometer display in a Volvo S80 can be caused by several issues, including a blown fuse, a malfunctioning instrument cluster, or a faulty connection within the wiring harness. Additionally, problems with the vehicle's battery or alternator could lead to power issues affecting the display. In some cases, software glitches or issues with the vehicle's onboard computer may also be responsible. Diagnosing the exact cause typically requires professional evaluation.