How do you fix the digital speedometer light on a 1987 thunderbird?

To fix the digital speedometer light on a 1987 Thunderbird, first check the fuse related to the instrument panel, as a blown fuse can cause the light to fail. If the fuse is intact, inspect the connections to the speedometer and the circuit board for any loose or damaged wiring. Additionally, consider replacing the light bulb behind the speedometer display if applicable. If these steps don't resolve the issue, the problem might lie within the speedometer itself or the vehicle's electronic system, requiring further diagnostics.