replaced battery (now good) and glass, but display is very, very faint

Using your tools and components, I replaced the battery of our 2g iPod Touch. I broke the glass during disassembly, and replaced that with a fixit kit as well. After charging the device it powers on, but the brightness level of the display is "just above black." I could navigate to the brightness settings panel, and played with the settings (auto off, max brightness), but they had no effect.

did I make a mistake while re-assembling the components? It was working fine before the battery died (well over a year ago, granted).

Thanks.