Functional Test Fixture tests a PCBA which has seven-segment LEDs by isolating and measuring the light from each LED segment. Floated blocks self-align to the LED banks. Compliant material isolates each LED segment from the others. The light from each segment is channeled via fiber optic cables to LED sensors on a remote PCB. The light sensors on the remote PCB are then polled by the test system to confirm each segment is functional.