I have a Stern Star Trek LE that has no playfield LEDs lit up on it. All the LEDs are out. No inserts are lit up, no pop bumpers are lit up, nothing anywhere on the playfield. The system boots up, and plays normally, but it's dark. All fuses and voltages that can be tested on the CPU/Driver board, seem OK. The CPU board has some kind of serial communication that goes from J14 to a small node board. I replaced the cable with another straight through RJ12 cable, but no joy. Still no LEDs are lit.
The small node board looks like it has several LEDs on it (TX, RX, Stat/D1). None of these are lit up. It seems like the small node board should have LEDs lit up on it. Also, along the serial communication path, none of the red D21 LEDs on any of the LED control boards are lit up.
Any help is appreciated.